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Xiao D, Du H, Sun L, Suo X, Wang Y, Zhang Y, Zhang S, Kuang S, Hu F, Tu L, Yu D, Song P. Boosting the electron beam transmittance of field emission cathode using a self-charging gate. Nat Commun 2024; 15:764. [PMID: 38278943 PMCID: PMC10817892 DOI: 10.1038/s41467-024-45142-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2023] [Accepted: 01/16/2024] [Indexed: 01/28/2024] Open
Abstract
The gate-type carbon nanotubes cathodes exhibit advantages in long-term stable emission owing to the uniformity of electrical field on the carbon nanotubes, but the gate inevitably reduces the transmittance of electron beam, posing challenges for system stabilities. In this work, we introduce electron beam focusing technique using the self-charging SiNx/Au/Si gate. The potential of SiNx is measured to be approximately -60 V quickly after the cathode turning on, the negative potential can be maintained as the emission goes on. The charged surface generates rebounding electrostatic forces on the following electrons, significantly focusing the electron beam on the center of gate hole and allowing them to pass through gate with minimal interceptions. An average transmittance of 96.17% is observed during 550 hours prototype test, the transmittance above 95% is recorded for the cathode current from 2.14 μA to 3.25 mA with the current density up to 17.54 mA cm-2.
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Affiliation(s)
- Dongyang Xiao
- School of Optics and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
- MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
| | - Huanhuan Du
- School of Optics and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
- MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
| | - Leimeng Sun
- School of Optics and Electronic Information, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China.
| | - Xiaochen Suo
- MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
| | - Yurong Wang
- MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
| | - Yili Zhang
- MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
| | - Shaolin Zhang
- MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
| | - Shuangyang Kuang
- Hubei Key Laboratory of Plasma Chemistry and Advanced Materials, School of Materials Science and Engineering, Wuhan Institute of Technology, Wuhan, 430205, Hubei, China
| | - Fangjing Hu
- MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
| | - Liangcheng Tu
- MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China
- MOE Key Laboratory of TianQin Mission, TianQin Research Center for Gravitational Physics & School of Physics and Astronomy, Frontiers Science Center for TianQin, Gravitational Wave Research Center of CNSA, Sun Yat-sen University (Zhuhai Campus), Zhuhai, 519082, China
| | - Daren Yu
- Lab of Plasma Propulsion, Harbin Institute of Technology (HIT), Harbin, 150001, China
| | - Peiyi Song
- MOE Key Laboratory of Fundamental Physical Quantities Measurement & Hubei Key Laboratory of Gravitation and Quantum Physics, PGMF and School of Physics, Huazhong University of Science and Technology, Wuhan, 430074, Hubei, China.
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2
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Ma Y, Conroy S, Shaw A, Alliati IM, Sels BF, Zhang X, Tu X. Plasma-Enabled Selective Synthesis of Biobased Phenolics from Lignin-Derived Feedstock. JACS AU 2023; 3:3101-3110. [PMID: 38034967 PMCID: PMC10685411 DOI: 10.1021/jacsau.3c00468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 10/08/2023] [Accepted: 10/12/2023] [Indexed: 12/02/2023]
Abstract
Converting abundant biomass-derived feedstocks into value-added platform chemicals has attracted increasing interest in biorefinery; however, the rigorous operating conditions that are required limit the commercialization of these processes. Nonthermal plasma-based electrification using intermittent renewable energy is an emerging alternative for sustainable next-generation chemical synthesis under mild conditions. Here, we report a hydrogen-free tunable plasma process for the selective conversion of lignin-derived anisole into phenolics with a high selectivity of 86.9% and an anisole conversion of 45.6% at 150 °C. The selectivity to alkylated chemicals can be tuned through control of the plasma alkylation process by changing specific energy input. The combined experimental and computational results reveal that the plasma generated H and CH3 radicals exhibit a "catalytic effect" that reduces the activation energy of the transalkylation reactions, enabling the selective anisole conversion at low temperatures. This work opens the way for the sustainable and selective production of phenolic chemicals from biomass-derived feedstocks under mild conditions.
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Affiliation(s)
- Yichen Ma
- Department
of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, U.K.
| | - Stuart Conroy
- Department
of Chemical and Process Engineering, University
of Strathclyde, Glasgow G1 1XJ, U.K.
| | - Alexander Shaw
- School
of Mechanical and Aerospace Engineering, Queen’s University Belfast, Belfast BT9 5AG, U.K.
| | - Ignacio M. Alliati
- Department
of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, U.K.
| | - Bert F. Sels
- Center
for Sustainable Catalysis and Engineering, KU Leuven, Leuven 3001, Belgium
| | - Xiaolei Zhang
- Department
of Chemical and Process Engineering, University
of Strathclyde, Glasgow G1 1XJ, U.K.
- School
of Mechanical and Aerospace Engineering, Queen’s University Belfast, Belfast BT9 5AG, U.K.
| | - Xin Tu
- Department
of Electrical Engineering and Electronics, University of Liverpool, Liverpool L69 3GJ, U.K.
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3
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Saifutdinov A, Timerkaev B. Modeling and Comparative Analysis of Atmospheric Pressure Anodic Carbon Arc Discharge in Argon and Helium-Producing Carbon Nanostructures. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:1966. [PMID: 37446482 DOI: 10.3390/nano13131966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 06/23/2023] [Accepted: 06/25/2023] [Indexed: 07/15/2023]
Abstract
In this work, within the framework of a unified model for the discharge gap and electrodes, a comparative numerical analysis was carried out on the effect of evaporation of graphite anode material on the characteristics of the arc discharge in helium and argon. The effect of changing the plasma-forming ion, in which the ion of evaporated atomic carbon becomes the dominant ion, is demonstrated. For an arc discharge in helium, this effect is accompanied by a jump-like change in the dependence of the current density on voltage (CVC), and smoothly for a discharge in argon. With regard to the dynamics of the ignition of an arc discharge, it is shown that during the transition from glow discharge to arc in helium, the discharge parameters are also accompanied by an abrupt change, while in argon, this transition is smooth. This is due to the fact that the ionization potentials, as well as the ionization cross sections, differ significantly for helium and carbon, and are close in value for helium and argon. For various points on the CVC, the density distributions of the charged and neutral particles of an inert gas and evaporated gases are presented.
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Affiliation(s)
- Almaz Saifutdinov
- Department of General Physics, Kazan National Research Technical University named after A.N. Tupolev-KAI, K. Marx St., 10, 420071 Kazan, Russia
| | - Boris Timerkaev
- Department of General Physics, Kazan National Research Technical University named after A.N. Tupolev-KAI, K. Marx St., 10, 420071 Kazan, Russia
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4
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Fang ZX, Wang C, Wei YL, Wang QY, Zang SQ. Constructing Highly Reliable and Adaptive Primary Explosive Composites for Micro-Initiator Assisting by a Hybrid Template of Metal-Organic Frameworks and Cross-Linked Polymers. SMALL (WEINHEIM AN DER BERGSTRASSE, GERMANY) 2023; 19:e2300157. [PMID: 36916694 DOI: 10.1002/smll.202300157] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2023] [Revised: 02/22/2023] [Indexed: 06/15/2023]
Abstract
Primary explosive, as a reliable initiator for secondary explosives, is the central component of micro-initiators for modern aerospace systems and military operations. However, they are typically prepared as powders, posing potential safety risks because of the inevitable particles scattering issues in the actual working environments. Here, the fabrication of a highly adaptive bulk material of copper azide (CA)-based safe primary explosive for micro-initiators is demonstrated. This bulk material, as derived by a complete azidation reaction of the carbonized metal-organic framework/cross-linked polymer hybrid template, enables the firm embedding of active CA species in a cross-linked carbon network (denoted as CA-C). Interestingly, this CA-C bulk material demonstrates multifarious mechanical stabilities (e.g., good shock and vibration resistance, and anti-overload capacity) in the simulated working conditions. Meanwhile, the CA contents in the CA-C bulk material reached as high as 70.3%, ensuring its detonation power. As a proof of concept, CA-C bulk material assembling in a micro-detonator can efficiently detonate the secondary explosive of CL-20 under laser irradiation. This work hereby advances the fabrication of safe and powerful primary explosives for the fulfillment of safe micro-initiator in a broad range of applications in aerospace systems.
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Affiliation(s)
- Zi-Xin Fang
- Henan Key Laboratory of Crystalline Molecular Functional Materials, Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Chao Wang
- Henan Key Laboratory of Crystalline Molecular Functional Materials, Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Yong-Li Wei
- Henan Key Laboratory of Crystalline Molecular Functional Materials, Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Qian-You Wang
- Henan Key Laboratory of Crystalline Molecular Functional Materials, Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
| | - Shuang-Quan Zang
- Henan Key Laboratory of Crystalline Molecular Functional Materials, Green Catalysis Center and College of Chemistry, Zhengzhou University, Zhengzhou, 450001, P. R. China
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5
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Weerasinghe J, Prasad K, Mathew J, Trifoni E, Baranov O, Levchenko I, Bazaka K. Carbon Nanocomposites in Aerospace Technology: A Way to Protect Low-Orbit Satellites. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 13:nano13111763. [PMID: 37299666 DOI: 10.3390/nano13111763] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/10/2023] [Accepted: 05/22/2023] [Indexed: 06/12/2023]
Abstract
Recent advancements in space technology and reduced launching cost led companies, defence and government organisations to turn their attention to low Earth orbit (LEO) and very low Earth orbit (VLEO) satellites, for they offer significant advantages over other types of spacecraft and present an attractive solution for observation, communication and other tasks. However, keeping satellites in LEO and VLEO presents a unique set of challenges, in addition to those typically associated with exposure to space environment such as damage from space debris, thermal fluctuations, radiation and thermal management in vacuum. The structural and functional elements of LEO and especially VLEO satellites are significantly affected by residual atmosphere and, in particular, atomic oxygen (AO). At VLEO, the remaining atmosphere is dense enough to create significant drag and quicky de-orbit satellites; thus, thrusters are needed to keep them on a stable orbit. Atomic oxygen-induced material erosion is another key challenge to overcome during the design phase of LEO and VLEO spacecraft. This review covered the corrosion interactions between the satellites and the low orbit environment, and how it can be minimised through the use of carbon-based nanomaterials and their composites. The review also discussed key mechanisms and challenges underpinning material design and fabrication, and it outlined the current research in this area.
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Affiliation(s)
- Janith Weerasinghe
- School of Engineering, College of Engineering, Computing and Cybernetics, The Australian National University, Canberra, ACT 2600, Australia
| | - Karthika Prasad
- School of Engineering, College of Engineering, Computing and Cybernetics, The Australian National University, Canberra, ACT 2600, Australia
| | - Joice Mathew
- Advanced Instrumentation and Technology Centre, Research School of Astronomy & Astrophysics, ANU College of Science, The Australian National University, Canberra, ACT 2600, Australia
| | - Eduardo Trifoni
- Advanced Instrumentation and Technology Centre, Research School of Astronomy & Astrophysics, ANU College of Science, The Australian National University, Canberra, ACT 2600, Australia
| | - Oleg Baranov
- Department of Theoretical Mechanics, Engineering and Robomechanical Systems, National Aerospace University, 61070 Kharkiv, Ukraine
- Department of Gaseous Electronics, Jozef Stefan Institute, 1000 Ljubljana, Slovenia
| | - Igor Levchenko
- School of Engineering, College of Engineering, Computing and Cybernetics, The Australian National University, Canberra, ACT 2600, Australia
- Plasma Sources and Application Centre, NIE, Nanyang Technological University, Singapore 637616, Singapore
| | - Kateryna Bazaka
- School of Engineering, College of Engineering, Computing and Cybernetics, The Australian National University, Canberra, ACT 2600, Australia
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6
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Baranov O, Bazaka K, Belmonte T, Riccardi C, Roman HE, Mohandas M, Xu S, Cvelbar U, Levchenko I. Recent innovations in the technology and applications of low-dimensional CuO nanostructures for sensing, energy and catalysis. NANOSCALE HORIZONS 2023; 8:568-602. [PMID: 36928662 DOI: 10.1039/d2nh00546h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Low-dimensional copper oxide nanostructures are very promising building blocks for various functional materials targeting high-demanded applications, including energy harvesting and transformation systems, sensing and catalysis. Featuring a very high surface-to-volume ratio and high chemical reactivity, these materials have attracted wide interest from researchers. Currently, extensive research on the fabrication and applications of copper oxide nanostructures ensures the fast progression of this technology. In this article we briefly outline some of the most recent, mostly within the past two years, innovations in well-established fabrication technologies, including oxygen plasma-based methods, self-assembly and electric-field assisted growth, electrospinning and thermal oxidation approaches. Recent progress in several key types of leading-edge applications of CuO nanostructures, mostly for energy, sensing and catalysis, is also reviewed. Besides, we briefly outline and stress novel insights into the effect of various process parameters on the growth of low-dimensional copper oxide nanostructures, such as the heating rate, oxygen flow, and roughness of the substrates. These insights play a key role in establishing links between the structure, properties and performance of the nanomaterials, as well as finding the cost-and-benefit balance for techniques that are capable of fabricating low-dimensional CuO with the desired properties and facilitating their integration into more intricate material architectures and devices without the loss of original properties and function.
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Affiliation(s)
- Oleg Baranov
- Department of Theoretical Mechanics, Engineering and Robomechanical Systems, National Aerospace University, Kharkiv 61070, Ukraine.
- Department of Gaseous Electronics, Jozef Stefan Institute, Ljubljana 1000, Slovenia
| | - Kateryna Bazaka
- School of Engineering, The Australian National University, Canberra, ACT 2601, Australia
| | | | - Claudia Riccardi
- Dipartimento di Fisica "Giuseppe Occhialini", Università degli Studi di Milano-Bicocca, Piazza della Scienza 3, I20126 Milan, Italy
| | - H Eduardo Roman
- Dipartimento di Fisica "Giuseppe Occhialini", Università degli Studi di Milano-Bicocca, Piazza della Scienza 3, I20126 Milan, Italy
| | - Mandhakini Mohandas
- Center for Nanoscience and Technology, Anna University, Chennai, 600 025, India
| | - Shuyan Xu
- Plasma Sources and Application Centre, NIE, Nanyang Technological University, 637616, Singapore.
| | - Uroš Cvelbar
- Department of Gaseous Electronics, Jozef Stefan Institute, Ljubljana 1000, Slovenia
| | - Igor Levchenko
- Plasma Sources and Application Centre, NIE, Nanyang Technological University, 637616, Singapore.
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7
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Takahashi K. Thirty percent conversion efficiency from radiofrequency power to thrust energy in a magnetic nozzle plasma thruster. Sci Rep 2022; 12:18618. [PMID: 36357485 PMCID: PMC9649674 DOI: 10.1038/s41598-022-22789-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 10/19/2022] [Indexed: 11/11/2022] Open
Abstract
Innovations for terrestrial transportation technologies, e.g., cars, aircraft, and so on, have driven historical industries so far, and a similar breakthrough is now occurring in space owing to the successful development of electric propulsion devices such as gridded ion and Hall effect thrusters, where solar power is converted into the momentum of the propellant via acceleration of the ionized gases, resulting in a high specific impulse. A magnetic nozzle (MN) radiofrequency (rf) plasma thruster consisting of a low-pressure rf plasma source and a MN is an attractive candidate for a high-power electric propulsion device for spacecraft, as it will provide a long lifetime operation at a high-power level due to the absence of an electrode exposed to the plasma and a high thrust density. The high-density plasma produced in the source is transported along the magnetic field lines toward the open-source exit and the plasma is then spontaneously accelerated in the MN. By ejecting the plasma flow from the system, the reaction forces are exerted to the thruster structure including the source and the MN, and the spacecraft is resultantly propelled. The thruster will open the next door for space technologies, while the performance of the MN rf plasma thruster has been lower than those of the mature electric propulsion devices due to the energy loss to the physical walls. Here the thruster efficiency of about 30%, being the highest to date in this type of thruster, is successfully obtained in the MN rf plasma thruster by locating a cusp magnetic field inside the source, which acts as a virtual magnetic wall isolating the plasma from the source wall. The increase in the thrust by the cusp can be explained by considering the reductions of the loss area and the plasma volume in a thrust analysis combining a global source model and a one-dimensional MN model.
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8
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Zolotukhin DB, Bandaru SRP, Daniels KP, Beilis II, Keidar M. Demonstration of electric micropropulsion multimodality. SCIENCE ADVANCES 2022; 8:eadc9850. [PMID: 36070382 PMCID: PMC9451150 DOI: 10.1126/sciadv.adc9850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Accepted: 07/21/2022] [Indexed: 06/15/2023]
Abstract
Electric propulsion has become popular nowadays owing to the trend of miniaturizing the size and mass of satellites. However, the main drawback of the most popular approach-Hall thrusters-is that their efficiency and thrust-to-power ratio (TPR) markedly deteriorate when its size and power level are reduced. Here, we demonstrate an alternative approach-a minute low-power (<50 W), lightweight (~100 g), two-stage propulsion system. The system is based on a micro-cathode vacuum arc thruster with magnetoplasmadynamic second stage (μCAT-MPD), which achieves the following parameters: a thrust of up to 1.7 mN at a TPR of 37 μN/W and an efficiency of ~50%. A μCAT-MPD system, in addition to "traditional" inverse, displays the anomalous direct (growing) "TPR versus specific impulse Isp" trend at high Isp values and allows multimodality at high efficiency.
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Affiliation(s)
- Denis B. Zolotukhin
- George Washington University, 800 22nd Street Northwest, Washington, DC 20052, USA
- Tomsk State University of Control Systems and Radioelectronics, 40 Lenin Ave., Tomsk 634050, Russia
| | | | - Keir P. Daniels
- George Washington University, 800 22nd Street Northwest, Washington, DC 20052, USA
| | - Isak I. Beilis
- Department of Electrical Engineering, Tel Aviv University, Tel Aviv, Israel
| | - Michael Keidar
- George Washington University, 800 22nd Street Northwest, Washington, DC 20052, USA
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9
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Kleshch VI, Ismagilov RR, Mukhin VV, Orekhov AS, Filatyev AS, Obraztsov AN. Nano-graphite field-emission cathode for space electric propulsion systems. NANOTECHNOLOGY 2022; 33:415201. [PMID: 35785757 DOI: 10.1088/1361-6528/ac7def] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2022] [Accepted: 07/04/2022] [Indexed: 06/15/2023]
Abstract
Improving the thruster efficiency is a crucial challenge for the development of space electric propulsion systems, especially advanced air-breathing thrusters utilizing the surrounding rarefied atmosphere as fuel. A significant reduction in thruster power consumption can be achieved by using field emission (FE) cathodes that do not require heating and have the highest energy efficiency. In this work, we study FE from nano-graphite thin films, consisting of carbon nanostructures with a high aspect ratio, and demonstrate their suitability for use in the space electric propulsion systems. The films shown appropriate FE characteristics in a wide range of gas pressures at high current loads in constant and pulsed operation modes. Based on the obtained experimental results, nano-graphite cathodes were employed for the design of an electron gun with increased reliability and minimized energy losses associated with electron extraction. The possibility of using such a gun in a specific air-breathing satellite operating in low Earth orbits is demonstrated.
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Affiliation(s)
| | | | | | - Anton S Orekhov
- Moscow Institute of Physics and Technology, Dolgoprudny 141701, Russia
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10
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Corbella C, Portal S, Kundrapu MN, Keidar M. Nanosynthesis by atmospheric arc discharges excited with pulsed-DC power: a review. NANOTECHNOLOGY 2022; 33:342001. [PMID: 35487195 DOI: 10.1088/1361-6528/ac6bad] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Accepted: 04/29/2022] [Indexed: 06/14/2023]
Abstract
Plasma technology is actively used for nanoparticle synthesis and modification. All plasma techniques share the ambition of providing high quality, nanostructured materials with full control over their crystalline state and functional properties. Pulsed-DC physical/chemical vapour deposition, high power impulse magnetron sputtering, and pulsed cathodic arc are consolidated low-temperature plasma processes for the synthesis of high-quality nanocomposite films in vacuum environment. However, atmospheric arc discharge stands out thanks to the high throughput, wide variety, and excellent quality of obtained stand-alone nanomaterials, mainly core-shell nanoparticles, transition metal dichalcogenide monolayers, and carbon-based nanostructures, like graphene and carbon nanotubes. Unique capabilities of this arc technique are due to its flexibility and wide range of plasma parameters achievable by modulation of the frequency, duty cycle, and amplitude of pulse waveform. The many possibilities offered by pulsed arc discharges applied on synthesis of low-dimensional materials are reviewed here. Periodical variations in temperature and density of the pulsing arc plasma enable nanosynthesis with a more rational use of the supplied power. Parameters such as plasma composition, consumed power, process stability, material properties, and economical aspects, are discussed. Finally, a brief outlook towards future tendencies of nanomaterial preparation is proposed. Atmospheric pulsed arcs constitute promising, clean processes providing ecological and sustainable development in the production of nanomaterials both in industry and research laboratories.
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Affiliation(s)
- Carles Corbella
- Department of Mechanical and Aerospace Engineering, George Washington University, 800 22nd Street, Northwest, Washington, DC 20052, United States of America
| | - Sabine Portal
- Department of Mechanical and Aerospace Engineering, George Washington University, 800 22nd Street, Northwest, Washington, DC 20052, United States of America
| | - Madhusudhan N Kundrapu
- Tech-X Corporation, 5621 Arapahoe Ave. Suite A, Boulder, CO 80303, United States of America
| | - Michael Keidar
- Department of Mechanical and Aerospace Engineering, George Washington University, 800 22nd Street, Northwest, Washington, DC 20052, United States of America
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11
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Effects of Titanium Dioxide Nanoparticles on Cell Growth and Migration of A549 Cells under Simulated Microgravity. NANOMATERIALS 2022; 12:nano12111879. [PMID: 35683734 PMCID: PMC9182076 DOI: 10.3390/nano12111879] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 05/24/2022] [Accepted: 05/27/2022] [Indexed: 01/27/2023]
Abstract
With the increasing application of nanomaterials in aerospace technology, the long-term space exposure to nanomaterials especially in the space full of radiation coupled with microgravity condition has aroused great health concerns of the astronauts. However, few studies have been conducted to assess these effects, which are crucial for seeking the possible intervention strategy. Herein, using a random positioning machine (RPM) to simulate microgravity, we investigated the behaviors of cells under simulated microgravity and also evaluated the possible toxicity of titanium dioxide nanoparticles (TiO2 NPs), a multifunctional nanomaterial with potential application in aerospace. Pulmonary epithelial cells A549 were exposed to normal gravity (1 g) and simulated gravity (~10−3 g), respectively. The results showed that simulated microgravity had no significant effect on the viability of A549 cells as compared with normal gravity within 48 h. The effects of TiO2 NPs exposure on cell viability and apoptosis were marginal with only a slightly decrease in cell viability and a subtle increase in apoptosis rate observed at a high concentration of TiO2 NPs (100 μg/mL). However, it was observed that the exposure to simulated microgravity could obviously reduce A549 cell migration compared with normal gravity. The disruption of F-actin network and the deactivation of FAK (Tyr397) might be responsible for the impaired mobility of simulated microgravity-exposed A549 cells. TiO2 NPs exposure inhibited cell migration under two different gravity conditions, but to different degrees, with a milder inhibition under simulated microgravity. Meanwhile, it was found that A549 cells internalized more TiO2 NPs under normal gravity than simulated microgravity, which may account for the lower cytotoxicity and the lighter inhibition of cell migration induced by the same exposure concentration of TiO2 NPs under simulated microgravity at least partially. Our study has provided some tentative information on the effects of TiO2 NPs exposure on cell behaviors under simulated microgravity.
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12
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Adaptive Neural Network Global Nonsingular Fast Terminal Sliding Mode Control for a Real Time Ground Simulation of Aerodynamic Heating Produced by Hypersonic Vehicles. ENERGIES 2022. [DOI: 10.3390/en15093284] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
This paper presents a strategy for a thermal-structural test with quartz lamp heaters (TSTQLH), combined with an ultra-local model, a closed-loop controller, a linear extended state observer (LESO), and an auxiliary controller. The TSTQLH is a real time ground simulation of aerodynamic heating for hypersonic vehicles to optimize their thermal protection systems (TPS). However, lack of a system dynamic model for the TSTQLH results in inaccurate tracking of aerodynamic heating. In addition, during the control process, the TSTQLH has internal uncertainties of resistance and external disturbances. Therefore, it is necessary to establish a mathematical model between controllable α(t) and measurable T1(t). An ultra-local model of model-free control plays a crucial role in simplifying system complexity and reducing high-order terms due to high nonlinearities and strong couplings in the system dynamic model, and a global nonsingular fast terminal sliding mode control (GNFTSMC) is added to an ultra-local model, which is used to guarantee great tracking performance in the sliding phase and fast convergence to the equilibrium state in finite time. Moreover, the LESO is used mainly to estimate all disturbances in real time, and an adaptive neural network (ANN) shows a good approximation property in compensation for estimation errors by using a cubic B-spline function. The fitted curve of the wall temperature in the time sequence represents a reference temperature trajectory from the surface contour of an X-43A’s wing. The comparative results validate that the proposed control strategy possesses strong robustness to track the reference temperature trajectory.
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13
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Bodrikov IV, Ivanova AG, Vasiliev AL, Titov EY, Titov DY, Serov AI. Influence of low-voltage discharge energy on the morphology of carbon nanostructures in induced benzene transformation. RSC Adv 2021; 11:39428-39437. [PMID: 35492493 PMCID: PMC9044420 DOI: 10.1039/d1ra06586f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2021] [Accepted: 12/04/2021] [Indexed: 01/15/2023] Open
Abstract
The directions of the transformation of benzene induced by low-voltage discharges at various energies of pulsed discharges were revealed. This paper shows the dependencies of the morphology and other characteristics of nanostructures obtained in the induced transformation of benzene on the energy of pulsed discharges. Nanostructures with different morphologies are formed when the energy of the low-voltage discharges changes during the induced transformation of benzene in the liquid phase. Two types of carbon nanostructures were formed in the induced destruction of benzene with a 90 μF capacitor. The first type of structure includes graphite fibers, two- and three-layer graphene sheets, as well as two- and three-layer hollow spheres and microstructures in the form of CNHs. The microstructures of the second type were onion-like spheroids. An increase in the capacitance up to 20 090 μF led to the formation of two types of nanostructures: onion-like spheroids and carbon fibers. A further increase in the capacitance to 40 090 μF caused the formation of onion-like spheroids. The first type microstructure in the sample 90 μF: (a) BF TEM image of the graphene layers with hollow spheres (arrowed) and the area with graphite (marked by G).![]()
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Affiliation(s)
- Ivan Vasilievich Bodrikov
- Nizhny Novgorod State Technical University n. a. R. E. Alekseev Minin St., 24 603950 Nizhny Novgorod Russia
| | - Anna Gennadevna Ivanova
- Shubnikov Institute of Crystallography of FSRC "Crystallography and Photonics" RAS 59 Leninsky Prospect 119333 Moscow Russia
| | - Alexander Leonidovich Vasiliev
- Shubnikov Institute of Crystallography of FSRC "Crystallography and Photonics" RAS 59 Leninsky Prospect 119333 Moscow Russia.,National Research Center "Kurchatov Institute" 1, Akademika Kurchatova Sq. 123182 Moscow Russia.,Moscow Institute of Physics and Technology, National Research University Dolgoprudny Moscow Region Russia
| | - Evgeny Yurievich Titov
- Nizhny Novgorod State Technical University n. a. R. E. Alekseev Minin St., 24 603950 Nizhny Novgorod Russia
| | - Dmitry Yurievich Titov
- Nizhny Novgorod State Technical University n. a. R. E. Alekseev Minin St., 24 603950 Nizhny Novgorod Russia
| | - Anton Igorevich Serov
- Nizhny Novgorod State Technical University n. a. R. E. Alekseev Minin St., 24 603950 Nizhny Novgorod Russia
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14
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Kumar A, Al-Jumaili A, Bazaka O, Ivanova EP, Levchenko I, Bazaka K, Jacob MV. Functional nanomaterials, synergisms, and biomimicry for environmentally benign marine antifouling technology. MATERIALS HORIZONS 2021; 8:3201-3238. [PMID: 34726218 DOI: 10.1039/d1mh01103k] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Marine biofouling remains one of the key challenges for maritime industries, both for seafaring and stationary structures. Currently used biocide-based approaches suffer from significant drawbacks, coming at a significant cost to the environment into which the biocides are released, whereas novel environmentally friendly approaches are often difficult to translate from lab bench to commercial scale. In this article, current biocide-based strategies and their adverse environmental effects are briefly outlined, showing significant gaps that could be addressed through advanced materials engineering. Current research towards the use of natural antifouling products and strategies based on physio-chemical properties is then reviewed, focusing on the recent progress and promising novel developments in the field of environmentally benign marine antifouling technologies based on advanced nanocomposites, synergistic effects and biomimetic approaches are discussed and their benefits and potential drawbacks are compared to existing techniques.
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Affiliation(s)
- Avishek Kumar
- Electronics Materials Lab, College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia.
| | - Ahmed Al-Jumaili
- Electronics Materials Lab, College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia.
- Medical Physics Department, College of Medical Sciences Techniques, The University of Mashreq, Baghdad, Iraq
| | - Olha Bazaka
- School of Science, RMIT University, PO Box 2476, Melbourne, VIC 3001, Australia
| | - Elena P Ivanova
- School of Science, RMIT University, PO Box 2476, Melbourne, VIC 3001, Australia
| | - Igor Levchenko
- Plasma Sources and Application Centre, NIE, Nanyang Technological University, 637616, Singapore
| | - Kateryna Bazaka
- Electronics Materials Lab, College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia.
- Faculty of Engineering, Queensland University of Technology, Brisbane, QLD 4000, Australia
- School of Engineering, The Australian National University, Canberra, ACT 2601, Australia
| | - Mohan V Jacob
- Electronics Materials Lab, College of Science and Engineering, James Cook University, Townsville, QLD 4811, Australia.
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15
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Kim KS, Sigouin G, Cho H, Couillard M, Gallerneault M, Moon SY, Lee HS, Kim MJ, Jang SG, Shin H. Insight into BN Impurity Formation during Boron Nitride Nanotube Synthesis by High-Temperature Plasma. ACS OMEGA 2021; 6:27418-27429. [PMID: 34693163 PMCID: PMC8529687 DOI: 10.1021/acsomega.1c04361] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2021] [Accepted: 09/24/2021] [Indexed: 06/01/2023]
Abstract
The high-temperature plasma process has demonstrated great potential in growing high-quality boron nitride nanotubes (BNNTs) with small diameters (∼5 nm) and few walls (3-4 walls) and led to successful commercialization with a high production rate approaching 20 g/h. However, the process is still accompanied by the production of BN impurities (e.g., a-BN, BN shell, BN flakes) whose physicochemical properties are similar to those of BNNTs. This renders the post-purification process very challenging and thus hampers the development of their practical applications. In this study, we have employed both experimental and numerical approaches for a mechanistic understanding of BN impurity formation in the high-temperature plasma process. This study suggests that the flow structure of the plasma jet (e.g., laminar or turbulent) plays a key role in the formation of BN impurities by dictating the transport phenomena of BNNT seeds (e.g., B droplets), which play an important role in BNNT nucleation. We discussed that the turbulence enhances the radial diffusion of B droplets as well as their interparticle coagulation, which leads to a significant reduction in the population of effective BNNT seeds in the BNNT growth zone (T < 4000 K). This results in the generation of unreacted BN precursors (e.g., B-N-H species) in the BNNT growth zone that eventually self-assemble into BN impurities. Our numerical simulation also suggests that a higher thermal energy input makes the flow more turbulent in the BNNT growth zone due to the elevated velocity difference between the plasma jet and ambient cold gas. This finding provides critical insight into the process design that can suppress the BN impurity formation in the high-temperature plasma process.
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Affiliation(s)
- Keun Su Kim
- Security
and Disruptive Technologies Centre, National
Research Council Canada, Ottawa, Ontario K1A 0R6, Canada
- Department
of Mechanical and Industrial Engineering, University of Toronto, Toronto, Ontario M5S 3G8, Canada
| | - Gabriela Sigouin
- Department
of Chemical and Biological Engineering, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Hyunjin Cho
- Security
and Disruptive Technologies Centre, National
Research Council Canada, Ottawa, Ontario K1A 0R6, Canada
| | - Martin Couillard
- Energy,
Mining and Environment Research Centre, National Research Council Canada, Ottawa, Ontario K1A 0R6, Canada
| | - Mary Gallerneault
- Security
and Disruptive Technologies Centre, National
Research Council Canada, Ottawa, Ontario K1A 0R6, Canada
| | - Se Youn Moon
- Department
of Quantum System Engineering, Jeonbuk National
University, Jeonju, Jeollabuk-do 54869, Republic of Korea
| | - Hun Su Lee
- Functional
Composite Materials Research Center, Korea
Institute of Science and Technology, Wanju, Jeollabuk-do 55324, Republic of Korea
| | - Myung Jong Kim
- Department
of Chemistry, Gachon University, 1342 Seongnam-daero, Sujeong-gu, Seongnam-si, Gyeonggi-do 13120, Republic of Korea
| | - Se Gyu Jang
- Functional
Composite Materials Research Center, Korea
Institute of Science and Technology, Wanju, Jeollabuk-do 55324, Republic of Korea
| | - Homin Shin
- Security
and Disruptive Technologies Centre, National
Research Council Canada, Ottawa, Ontario K1A 0R6, Canada
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16
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Yao P, Sands T. Micro Satellite Orbital Boost by Electrodynamic Tethers. MICROMACHINES 2021; 12:mi12080916. [PMID: 34442538 PMCID: PMC8400572 DOI: 10.3390/mi12080916] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Revised: 07/18/2021] [Accepted: 07/28/2021] [Indexed: 11/18/2022]
Abstract
In this manuscript, a method for maneuvering a spacecraft using electrically charged tethers is explored. The spacecraft’s velocity vector can be modified by interacting with Earth’s magnetic field. Through this method, a spacecraft can maintain an orbit indefinitely by reboosting without the constraint of limited propellant. The spacecraft-tether system dynamics in low Earth orbit are simulated to evaluate the effects of Lorentz force and torques on translational motion. With 500-meter tethers charged with a 1-amp current, a 100-kg spacecraft can gain 250 m of altitude in one orbit. By evaluating the combined effects of Lorenz force and the coupled effects of Lorentz torque propagation through Euler’s moment equation and Newton’s translational motion equations, the simulated spacecraft-tether system can orbit indefinitely at altitudes as low as 275 km. Through a rare evaluation of the nonlinear coupling of the six differential equations of motion, the one finding is that an electrodynamic tether can be used to maintain a spacecraft’s orbit height indefinitely for very low Earth orbits. However, the reboost maneuver is inefficient for high inclination orbits and has high electrical power requirement. To overcome greater aerodynamic drag at lower altitudes, longer tethers with higher power draw are required.
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17
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Levchenko I, Xu S, Baranov O, Bazaka O, Ivanova EP, Bazaka K. Plasma and Polymers: Recent Progress and Trends. Molecules 2021; 26:molecules26134091. [PMID: 34279431 PMCID: PMC8271681 DOI: 10.3390/molecules26134091] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 06/20/2021] [Accepted: 06/22/2021] [Indexed: 02/06/2023] Open
Abstract
Plasma-enhanced synthesis and modification of polymers is a field that continues to expand and become increasingly more sophisticated. The highly reactive processing environments afforded by the inherently dynamic nature of plasma media are often superior to ambient or thermal environments, offering substantial advantages over other processing methods. The fluxes of energy and matter toward the surface enable rapid and efficient processing, whereas the charged nature of plasma-generated particles provides a means for their control. The range of materials that can be treated by plasmas is incredibly broad, spanning pure polymers, polymer-metal, polymer-wood, polymer-nanocarbon composites, and others. In this review, we briefly outline some of the recent examples of the state-of-the-art in the plasma-based polymer treatment and functionalization techniques.
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Affiliation(s)
- Igor Levchenko
- Plasma Sources and Application Centre, National Institute of Education, Nanyang Technological University, Singapore 637616, Singapore;
- Correspondence: (I.L.); (K.B.)
| | - Shuyan Xu
- Plasma Sources and Application Centre, National Institute of Education, Nanyang Technological University, Singapore 637616, Singapore;
| | - Oleg Baranov
- Faculty of Aircraft Engines, National Aerospace University, 61070 Kharkiv, Ukraine;
| | - Olha Bazaka
- School of Science, RMIT University, P.O. Box 2476, Melbourne, VIC 3001, Australia; (O.B.); (E.P.I.)
| | - Elena P. Ivanova
- School of Science, RMIT University, P.O. Box 2476, Melbourne, VIC 3001, Australia; (O.B.); (E.P.I.)
| | - Kateryna Bazaka
- Plasma Sources and Application Centre, National Institute of Education, Nanyang Technological University, Singapore 637616, Singapore;
- School of Mechanical, Medical and Process Engineering, Queensland University of Technology, Brisbane, QLD 4000, Australia
- School of Engineering, The Australian National University, Canberra, ACT 2601, Australia
- Correspondence: (I.L.); (K.B.)
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18
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Delkowski M, Smith CT, Anguita JV, Silva SRP. Increasing the robustness and crack resistivity of high-performance carbon fiber composites for space applications. iScience 2021; 24:102692. [PMID: 34195569 PMCID: PMC8233203 DOI: 10.1016/j.isci.2021.102692] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2021] [Revised: 05/17/2021] [Accepted: 06/03/2021] [Indexed: 11/28/2022] Open
Abstract
The endeavors to develop manufacturing methods that can enhance polymer and composite structures in spacecraft have led to much research and innovation over many decades. However, the thermal stability, intrinsic material stress, and anisotropic substrate properties pose significant challenges and inhibit the use of previously proposed solutions under extreme space environment. Here, we overcome these issues by developing a custom-designed, plasma-enhanced cross-linked poly(p-xylylene):diamond-like carbon superlattice material that enables enhanced mechanical coupling with the soft polymeric and composite materials, which in turn can be applied to large 3D engineering structures. The superlattice structure developed forms an integral part with the substrate and results in a space qualifiable carbon-fiber-reinforced polymer featuring 10-20 times greater resistance to cracking without affecting the stiffness of dimensionally stable structures. This innovation paves the way for the next generation of advanced ultra-stable composites for upcoming optical and radar instrument space programs and advanced engineering applications.
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Affiliation(s)
- Michal Delkowski
- Advanced Technology Institute, Department of Electrical and Electronic Engineering, University of Surrey, Guildford, Surrey GU2 7XH, UK
- Airbus Defence and Space GmbH, Claude-Dornier-Strasse, 88090 Immenstaad, Germany
| | - Christopher T.G. Smith
- Advanced Technology Institute, Department of Electrical and Electronic Engineering, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - José V. Anguita
- Advanced Technology Institute, Department of Electrical and Electronic Engineering, University of Surrey, Guildford, Surrey GU2 7XH, UK
| | - S. Ravi P. Silva
- Advanced Technology Institute, Department of Electrical and Electronic Engineering, University of Surrey, Guildford, Surrey GU2 7XH, UK
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19
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Magnetic nozzle radiofrequency plasma thruster approaching twenty percent thruster efficiency. Sci Rep 2021; 11:2768. [PMID: 33531602 PMCID: PMC7854726 DOI: 10.1038/s41598-021-82471-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Accepted: 01/18/2021] [Indexed: 11/30/2022] Open
Abstract
Development of a magnetic nozzle radiofrequency (rf) plasma thruster has been one of challenging topics in space electric propulsion technologies. The thruster typically consists of an rf plasma source and a magnetic nozzle, where the plasma produced inside the source is transported along the magnetic field and expands in the magnetic nozzle. An imparted thrust is significantly affected by the rf power coupling for the plasma production, the plasma transport, the plasma loss to the wall, and the plasma acceleration process in the magnetic nozzle. The rf power transfer efficiency and the imparted thrust are assessed for two types of rf antennas exciting azimuthal mode number of \documentclass[12pt]{minimal}
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\begin{document}$$m=0$$\end{document}m=0, where propellant argon gas is introduced from the upstream of the thruster source tube. The rf power transfer efficiency and the density measured at the radial center for the \documentclass[12pt]{minimal}
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\begin{document}$$m=+1$$\end{document}m=+1 mode antenna are higher than those for the \documentclass[12pt]{minimal}
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\begin{document}$$m=0$$\end{document}m=0 mode antenna, while a larger thrust is obtained for the \documentclass[12pt]{minimal}
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\begin{document}$$m=0$$\end{document}m=0 mode antenna. Two-dimensional plume characterization suggests that the lowered performance for the \documentclass[12pt]{minimal}
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\begin{document}$$m=+1$$\end{document}m=+1 mode case is due to the plasma production at the radial center, where contribution on a thrust exerted to the magnetic nozzle is weak due to the absence of the radial magnetic field. Subsequently, the configuration is modified so as to introduce the propellant gas near the thruster exit for the \documentclass[12pt]{minimal}
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\begin{document}$$m=0$$\end{document}m=0 mode configuration and the thruster efficiency approaching twenty percent is successfully obtained, being highest to date in the kW-class magnetic nozzle rf plasma thrusters.
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20
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Abstract
Over 2500 active satellites are in orbit as of October 2020, with an increase of ~1000 smallsats in the past two years. Since 2012, over 1700 smallsats have been launched into orbit. It is projected that by 2025, there will be 1000 smallsats launched per year. Currently, these satellites do not have sufficient delta v capabilities for missions beyond Earth orbit. They are confined to their pre-selected orbit and in most cases, they cannot avoid collisions. Propulsion systems on smallsats provide orbital manoeuvring, station keeping, collision avoidance and safer de-orbit strategies. In return, this enables longer duration, higher functionality missions beyond Earth orbit. This article has reviewed electrostatic, electrothermal and electromagnetic propulsion methods based on state of the art research and the current knowledge base. Performance metrics by which these space propulsion systems can be evaluated are presented. The article outlines some of the existing limitations and shortcomings of current electric propulsion thruster systems and technologies. Moreover, the discussion contributes to the discourse by identifying potential research avenues to improve and advance electric propulsion systems for smallsats. The article has placed emphasis on space propulsion systems that are electric and enable interplanetary missions, while alternative approaches to propulsion have also received attention in the text, including light sails and nuclear electric propulsion amongst others.
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21
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Zhang H, Li DT, Li H. Development of a cantilever beam thrust stand for electric propulsion thrusters. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2020; 91:115104. [PMID: 33261444 DOI: 10.1063/5.0027911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Accepted: 11/03/2020] [Indexed: 06/12/2023]
Abstract
The application of electric thrusters on spacecrafts has become more and more extensive. Accurate, direct measurement of thrust is not only one of the most critical elements of electric thruster characterization but also one of the most difficult measurements to make in the ground test and verification of electric propulsion. It is hard to measure the thrust in a finite simulation environment due to small thrust and interference factors in the measurement. A cantilever beam thrust stand has been designed and tested in our propulsion laboratory. The device is used to measure the thrust of a plasma thruster multiple times a day. The thrust stand allows adjusting the instrument sensibility by changing the size of the cantilever beam. The range of thrust depends on the thrusters; e.g., for a 15 kg ion thruster, the thrust can vary from 10 mN up to 220 mN. Calibration of the system is carried out using calibrated mass. The balance results are compared to the thrust calculated using electrical parameters, showing an agreement within 3.16%.
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Affiliation(s)
- H Zhang
- Electric Propulsion Laboratory, Lanzhou Institute of Physics, Lanzhou 730000, China
| | - D T Li
- Electric Propulsion Laboratory, Lanzhou Institute of Physics, Lanzhou 730000, China
| | - H Li
- Electric Propulsion Laboratory, Lanzhou Institute of Physics, Lanzhou 730000, China
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22
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Pan R, Ren J, Tang H, Cao S, Li J, Zhang Z, Zhou J, Cao J. Application of the view factor model on the particle-in-cell and Monte Carlo collision code. Phys Rev E 2020; 102:033311. [PMID: 33076033 DOI: 10.1103/physreve.102.033311] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 08/03/2020] [Indexed: 11/07/2022]
Abstract
Particle-in-cell and Monte Carlo collision (PIC-MCC) has been widely adopted as a simulation method for electric propulsion. However, neutral atoms move much more slowly than other species, which can cause a serious reduction in simulation speed. In this work, we investigate the view factor model in combination with the PIC-MCC method and propose a method for simulating three-dimensional neutral atoms. The accuracy of the PIC-MCC method can be significantly improved by updating the neutral distribution periodically. We compare the computational results with the fixed-neutral PIC-MCC model of the miniature ring-cusp discharge experiment at the University of California, Los Angeles (UCLA). The plasma distribution and potential distribution of the simulation match well with the UCLA experimental data. Compared with the fixed-neutral model, the view factor model increases the simulation time by only 33% while it improves the distribution accuracy of neutrals, plasma density, and electric potential, and reduces the simulation errors of discharge current and discharge power from 19.8% to 9.8%. The accuracy of PIC-MCC simulation has been improved at the expense of slightly increasing the computational time.
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Affiliation(s)
- Ruojian Pan
- School of Space and Environment, Beihang University, Beijing 100083, China
| | - Junxue Ren
- School of Astronautics, Beihang University, Beijing 100083, China
| | - Haibin Tang
- School of Space and Environment, Beihang University, Beijing 100083, China.,Key Laboratory of Spacecraft Design Optimization and Dynamic Simulation Technologies, Ministry of Education, Beijing 100083, China.,Laboratory of Space Environment monitoring and Information Processing, Ministry of Industry and Information Technology, Beijing 100083, China
| | - Shuai Cao
- School of Astronautics, Beihang University, Beijing 100083, China
| | - Juan Li
- National Key Laboratory of Science and Technology on Vacuum Technology & Physics, Lanzhou Institute of Physics, Lanzhou 730000, China
| | - Zhe Zhang
- School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing 100083, China
| | - Jun Zhou
- School of Astronautics, Beihang University, Beijing 100083, China
| | - Jinbin Cao
- School of Space and Environment, Beihang University, Beijing 100083, China.,Laboratory of Space Environment monitoring and Information Processing, Ministry of Industry and Information Technology, Beijing 100083, China
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23
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Liu Y, Lin L, Yu Y, Zhang Q, Mang S. Plasma-Liquid Interface Manipulated by Chamber Structure: An Experimental and Theoretical Approach. ACS APPLIED MATERIALS & INTERFACES 2020; 12:44238-44247. [PMID: 32865958 DOI: 10.1021/acsami.0c09341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To respond to global challenges of environmental contaminations, pursue more advanced material technologies, and achieve novel biomedical therapies, a variety of plasmas have been applied to wastewater and food processing, biomaterial treatments, and plasma-liquid ignitions. As these applications highly depend on the plasma-liquid interactions, researchers are now focusing on the physical and chemical reactions on the plasma-liquid interface. With massive publications reporting the molecular transfers, chemical pathways, and their effects on plasma treatments, this work provides a new point of view that the plasma-liquid interface can be manipulated by the chamber structure. In the experiment, plasma jet expansion in water is recorded in a cylinder chamber and a stepped-wall one. Data collected from the images show that the stepped-wall structure results in a shorter axial interface propagation, a small volume, more symmetry for the plasma jet, and more stability for the interface. To discover the physical mechanism behind these phenomena, we derived the momentum and energy equations for the plasma-liquid interface during its propagation. Those equations reveal how the stepped-wall structure can be used to manipulate the interface behaviors. Along with our experimental and theoretical investigation of the plasma-liquid interface, such information also sheds light on how the chamber wall structure can be used to manipulate the interface chemical reaction rates, stability, and expansion rate. This work is thus a basis of the future optimization for plasma-liquid treatments and ignitions which will be equipped with a flexible wall controlled by artificial intelligence to automatically achieve a variety of plasma treatment requirements.
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Affiliation(s)
- Yi Liu
- School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Li Lin
- School of Engineering and Applied Science, The George Washington University, Washington, DC 20052, United States
| | - Yonggang Yu
- School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Qi Zhang
- School of Energy and Power Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
| | - Shanshan Mang
- School of Science, Nanjing University of Science and Technology, Nanjing 210094, China
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24
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Zolotukhin DB, Daniels KP, Brieda L, Keidar M. Onset of the magnetized arc and its effect on the momentum of a low-power two-stage pulsed magneto-plasma-dynamic thruster. Phys Rev E 2020; 102:021203. [PMID: 32942417 DOI: 10.1103/physreve.102.021203] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Accepted: 07/14/2020] [Indexed: 11/07/2022]
Abstract
A new type of plasma accelerator-a low-power (<30W), miniature (cm-sized), two-stage pulsed magneto-plasma-dynamic thruster-has been proposed. Being magnetized by an axially symmetric dc magnetic field of ∼200 mT, the vacuum arc discharge demonstrates a threshold behavior: Parameters such as thrust and the thrust-to-power ratio rapidly jump after a certain dc voltage (∼30 V) is applied on the accelerating electrode. We show that such an effect improves the thrust (from ∼2 to ∼210 µN), efficiency (from ∼1% to 50%), and thrust-to-power ratio (from ∼0.5 to ∼18 µN/W).
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Affiliation(s)
- D B Zolotukhin
- The George Washington University, 800 22nd Street, Northwest, Washington, DC 20052, USA.,Tomsk State University of Control Systems and Radioelectronics, 40 Lenin Avenue, Tomsk 634050, Russia
| | - K P Daniels
- The George Washington University, 800 22nd Street, Northwest, Washington, DC 20052, USA
| | - L Brieda
- Particle In Cell Consulting LLC, Westlake Village, California 91362, USA
| | - M Keidar
- The George Washington University, 800 22nd Street, Northwest, Washington, DC 20052, USA
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25
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Klimkevicius V, Janulevicius M, Babiceva A, Drabavicius A, Katelnikovas A. Effect of Cationic Brush-Type Copolymers on the Colloidal Stability of GdPO 4 Particles with Different Morphologies in Biological Aqueous Media. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2020; 36:7533-7544. [PMID: 32493012 PMCID: PMC7467769 DOI: 10.1021/acs.langmuir.0c01130] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/18/2020] [Revised: 06/03/2020] [Indexed: 06/11/2023]
Abstract
In this study, we present the synthesis of cationic brush-type polyelectrolytes and their use in the stabilization of GdPO4 particles in aqueous media. Polymers of various compositions were synthesized via the RAFT polymerization route. SEC equipped with triple detection (RI, DP, RALS, and LALS) was used to determine the molecular parameters (Mn, Mw, Mw/Mn). The exact composition of synthesized polymers was determined using NMR spectroscopy. Cationic brush-type polymers were used to improve the stability of aqueous GdPO4 particle dispersions. First, the IEPs of GdPO4 particles with different morphologies (nanorods, hexagonal nanoprisms, and submicrospheres) were determined by measuring the zeta potential of bare particle dispersions at various pH values. Afterward, cationic brush-type polyelectrolytes with different compositions were used for the surface modification of GdPO4 particles (negatively charged in alkaline media under a pH value of ∼10.6). The concentration and composition effects of used polymers on the change in particle surface potential and stability (DLS measurements) in dispersions were investigated and presented in this work. The most remarkable result of this study is redispersible GdPO4 nanoparticle colloids with increased biocompatibility and stability as well as new insights into possible cationic brush-type polyelectrolyte applicability in both scientific and commercial fields.
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Affiliation(s)
- Vaidas Klimkevicius
- Institute
of Chemistry, Vilnius University, Naugarduko str. 24, LT-03225 Vilnius, Lithuania
| | - Matas Janulevicius
- Institute
of Chemistry, Vilnius University, Naugarduko str. 24, LT-03225 Vilnius, Lithuania
| | - Aleksandra Babiceva
- Institute
of Chemistry, Vilnius University, Naugarduko str. 24, LT-03225 Vilnius, Lithuania
| | - Audrius Drabavicius
- Centre
of Physical Science and Technology, Sauletekis av. 3, LT-10257 Vilnius, Lithuania
| | - Arturas Katelnikovas
- Institute
of Chemistry, Vilnius University, Naugarduko str. 24, LT-03225 Vilnius, Lithuania
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Kandasamy A, Ramasamy T, Samrin A, Narayanasamy P, Mohan R, Bazaka O, Levchenko I, Bazaka K, Mohandas M. Hierarchical Doped Gelatin-Derived Carbon Aerogels: Three Levels of Porosity for Advanced Supercapacitors. NANOMATERIALS 2020; 10:nano10061178. [PMID: 32560290 PMCID: PMC7353417 DOI: 10.3390/nano10061178] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 06/09/2020] [Accepted: 06/10/2020] [Indexed: 02/06/2023]
Abstract
Nitrogen-doped graphene-based aerogels with three levels of hierarchically organized pores were prepared via a simple environmentally friendly process, and successfully tested in supercapacitor applications. Mesopores and macropores were formed during the aerogel preparation followed by carbonization and its chemical activation by potassium hydroxide (KOH). These mesopores and macropores consist of amorphous carbon and a 3D graphene framework. Thermal treatment at 700 °C, 800 °C, 900 °C in N2 atmosphere was done to etch out the amorphous carbon and obtain a stable N-doped 3D graphene. Specific capacitance values obtained from the electrochemical measurements are in the range of 232–170 F× g−1. The thus fabricated structures showed excellent cyclic stability, suggesting that these materials have potential as electrodes for solid asymmetric supercapacitors.
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Affiliation(s)
- Ayshuwarya Kandasamy
- Center for Nanoscience and Technology, Anna University, Chennai 600025, India; (A.K.); (T.R.); (A.S.)
| | - Tamilselvi Ramasamy
- Center for Nanoscience and Technology, Anna University, Chennai 600025, India; (A.K.); (T.R.); (A.S.)
| | - Ayesha Samrin
- Center for Nanoscience and Technology, Anna University, Chennai 600025, India; (A.K.); (T.R.); (A.S.)
| | | | - Ramesh Mohan
- Smart Sensors, CSIR-Central Electronics Engineering Research Institute, Pilani, Rajasthan 333031, India;
| | - Olha Bazaka
- School of Science, RMIT University, PO Box 2476, Melbourne, VIC 3001, Australia;
| | - Igor Levchenko
- Plasma Sources and Application Centre/Space Propulsion Centre Singapore, NIE, Nanyang Technological University, Singapore 637616, Singapore;
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000, Australia
| | - Kateryna Bazaka
- Plasma Sources and Application Centre/Space Propulsion Centre Singapore, NIE, Nanyang Technological University, Singapore 637616, Singapore;
- Science and Engineering Faculty, Queensland University of Technology, Brisbane, QLD 4000, Australia
- Research School of Electrical, Energy and Materials Engineering, The Australian National University, Canberra, ACT 2601, Australia
- Correspondence: (K.B.); (M.M.)
| | - Mandhakini Mohandas
- Center for Nanoscience and Technology, Anna University, Chennai 600025, India; (A.K.); (T.R.); (A.S.)
- Correspondence: (K.B.); (M.M.)
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Abstract
The Hall thruster is a high-efficiency spacecraft propulsion device that utilizes plasma to generate thrust. The most common variant of the Hall thruster is the stationary plasma thruster (SPT). Erosion of the SPT discharge chamber wall by plasma sputtering degrades thruster performance and ultimately ends thruster life. Many efforts over the past few decades have endeavored to understand wall erosion so that novel thrusters can be designed to operate for the thousands of hours required by many missions. However, due to the challenges presented by the plasma and material physics associated with erosion, a complete understanding has thus far eluded researchers. Sputtering rates are not well quantified, erosion features remain unexplained, and computational models are not yet predictive. This article reviews the physics of plasma-induced SPT erosion, highlights important experimental findings, provides an overview of modeling efforts, and discusses erosion mitigation strategies.
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A Review of Low-Power Electric Propulsion Research at the Space Propulsion Centre Singapore. AEROSPACE 2020. [DOI: 10.3390/aerospace7060067] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
The age of space electric propulsion arrived and found the space exploration endeavors at a paradigm shift in the context of new space. Mega-constellations of small satellites on low-Earth orbit (LEO) are proposed by many emerging commercial actors. Naturally, the boom in the small satellite market drives the necessity of propulsion systems that are both power and fuel efficient and accommodate small form-factors. Most of the existing electric propulsion technologies have reached the maturity level and can be the prime choices to enable mission versatility for small satellite platforms in Earth orbit and beyond. At the Plasma Sources and Applications Centre/Space Propulsion Centre (PSAC/SPC) Singapore, a continuous effort was dedicated to the development of low-power electric propulsion systems that can meet the small satellites market requirements. This review presents the recent progress in the field of electric propulsion at PSAC/SPC Singapore, from Hall thrusters and thermionic cathodes research to more ambitious devices such as the rotamak-like plasma thruster. On top of that, a review of the existing vacuum facilities and plasma diagnostics used for electric propulsion testing and characterization is included in the present research.
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Bonasera A, Giuliano G, Arrabito G, Pignataro B. Tackling Performance Challenges in Organic Photovoltaics: An Overview about Compatibilizers. Molecules 2020; 25:E2200. [PMID: 32397234 PMCID: PMC7248780 DOI: 10.3390/molecules25092200] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2020] [Revised: 04/28/2020] [Accepted: 05/06/2020] [Indexed: 12/18/2022] Open
Abstract
Organic Photovoltaics (OPVs) based on Bulk Heterojunction (BHJ) blends are a mature technology. Having started their intensive development two decades ago, their low cost, processability and flexibility rapidly funneled the interest of the scientific community, searching for new solutions to expand solar photovoltaics market and promote sustainable development. However, their robust implementation is hampered by some issues, concerning the choice of the donor/acceptor materials, the device thermal/photo-stability, and, last but not least, their morphology. Indeed, the morphological profile of BHJs has a strong impact over charge generation, collection, and recombination processes; control over nano/microstructural morphology would be desirable, aiming at finely tuning the device performance and overcoming those previously mentioned critical issues. The employ of compatibilizers has emerged as a promising, economically sustainable, and widely applicable approach for the donor/acceptor interface (D/A-I) optimization. Thus, improvements in the global performance of the devices can be achieved without making use of more complex architectures. Even though several materials have been deeply documented and reported as effective compatibilizing agents, scientific reports are quite fragmentary. Here we would like to offer a panoramic overview of the literature on compatibilizers, focusing on the progression documented in the last decade.
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Affiliation(s)
- Aurelio Bonasera
- Department of Physics and Chemistry-Emilio Segrè, University of Palermo, viale delle Scienze, bdg. 17, 90128 Palermo, Italy; (G.G.); (G.A.)
- INSTM-Palermo Research Unit, viale delle Scienze, bdg. 17, 90128 Palermo, Italy
| | - Giuliana Giuliano
- Department of Physics and Chemistry-Emilio Segrè, University of Palermo, viale delle Scienze, bdg. 17, 90128 Palermo, Italy; (G.G.); (G.A.)
| | - Giuseppe Arrabito
- Department of Physics and Chemistry-Emilio Segrè, University of Palermo, viale delle Scienze, bdg. 17, 90128 Palermo, Italy; (G.G.); (G.A.)
| | - Bruno Pignataro
- Department of Physics and Chemistry-Emilio Segrè, University of Palermo, viale delle Scienze, bdg. 17, 90128 Palermo, Italy; (G.G.); (G.A.)
- INSTM-Palermo Research Unit, viale delle Scienze, bdg. 17, 90128 Palermo, Italy
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Xiang Q, Ma X, Zhang D, Zhou H, Liao Y, Zhang H, Xu S, Levchenko I, Bazaka K. Interfacial modification of titanium dioxide to enhance photocatalytic efficiency towards H2 production. J Colloid Interface Sci 2019; 556:376-385. [DOI: 10.1016/j.jcis.2019.08.033] [Citation(s) in RCA: 44] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2019] [Revised: 08/02/2019] [Accepted: 08/08/2019] [Indexed: 10/26/2022]
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31
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Lin L, Yan D, Gjika E, Sherman JH, Keidar M. Atmospheric Plasma Meets Cell: Plasma Tailoring by Living Cells. ACS APPLIED MATERIALS & INTERFACES 2019; 11:30621-30630. [PMID: 31374163 DOI: 10.1021/acsami.9b10620] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
The applications of the cold atmospheric plasma jet (CAPJ) in cancer treatment have been investigated for over a decade, focused on the effect that the CAPJ creates on cancer cells. Here we report for the first time on the impact that cells have on the CAPJ during treatment. To better understand these CAPJ-cell interactions, we analyzed the CAPJ behaviors in the presence of several normal and cancer cell lines and investigated the CAPJ selectivity. A more in-depth study of plasma self-organization patterns utilizing a model which contains a combination of normal and cancer cells reveals that the cells' capacitance can be an important predictor of plasma jet behavior. Cancer cells can direct the jet either toward or away from normal cells, which depends on the boundary condition behind the cell colony. Both experimental and theoretical results show that a grounded copper board beneath the cell-culture dish leads to opposite CPAJ behaviors compared with a floating boundary condition. In conclusion, our findings indicate that plasma can be self-adaptive toward cancer cells, and such a feature can be manipulated. Therefore, using the permittivity difference among cell lines may help us focus plasmas upon cancer cells at the vicinity of normal tissues and maximize the selectivity of plasma treatments.
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Affiliation(s)
- Li Lin
- Department of Mechanical and Aerospace Engineering , The George Washington University , 800 22nd Street NW , Washington , D.C. 20052 , United States of America
| | - Dayun Yan
- Department of Mechanical and Aerospace Engineering , The George Washington University , 800 22nd Street NW , Washington , D.C. 20052 , United States of America
| | - Eda Gjika
- Department of Mechanical and Aerospace Engineering , The George Washington University , 800 22nd Street NW , Washington , D.C. 20052 , United States of America
| | - Jonathan H Sherman
- Department of Mechanical and Aerospace Engineering , The George Washington University , 800 22nd Street NW , Washington , D.C. 20052 , United States of America
| | - Michael Keidar
- Department of Mechanical and Aerospace Engineering , The George Washington University , 800 22nd Street NW , Washington , D.C. 20052 , United States of America
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33
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Zhou HP, Ye X, Huang W, Wu MQ, Mao LN, Yu B, Xu S, Levchenko I, Bazaka K. Wearable, Flexible, Disposable Plasma-Reduced Graphene Oxide Stress Sensors for Monitoring Activities in Austere Environments. ACS APPLIED MATERIALS & INTERFACES 2019; 11:15122-15132. [PMID: 30869857 DOI: 10.1021/acsami.8b22673] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
In austere environments, for example, in outer space, on surfaces of extra-terrestrial bodies (Moon, Mars, etc.), or under water, technologies that can enable continuous, reliable, and authentic monitoring of movement of human operators and devices can be critical. We report here the production and human body test of wearable, flexible graphene oxide stress sensors suitable for real-time monitoring of body parameters, state and position of humans, and automatic equipment. These sensors have excellent sensitivity and signal strength across a wide strain range, alleviating the need for additional instrumentation for signal processing and amplification. Their low cost makes them virtually disposable, which may benefit such applications as smart clothing. The sensors were fabricated by a concomitant reduction and N-doping of graphene oxide on polydimethylsiloxane in N2-H2 plasma. The direct bias and other plasma parameters have a significant effect on the reduction and properties of graphene oxide sensors, as shown by optical emission, Raman and X-ray photoelectron spectroscopies, and X-ray diffraction. Optical emission showed different excitation and ionization processes involving atomic and molecular species in the N2-H2 discharge. The photoelectron spectroscopy has confirmed the graphene reduction and introduction of nitrogen doping into the reduced graphene oxide. The bias efficiently controls plasma-induced electric fields, and plasma-related effects determine the N-doping levels. The reduced graphene oxides demonstrate excellent tensile properties, which make them suitable for efficient but cheap stress sensors. This eco-friendly, fast, room-temperature method shows a great potential for fabrication of efficient, flexible sensors.
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Affiliation(s)
| | | | | | | | | | - B Yu
- College of Nanoscale Science and Engineering (CNSE) , State University of New York , Albany , New York 12203 , United States
| | - S Xu
- Plasma Sources and Application Center/Space Propulsion Centre Singapore, NIE, and Institute of Advanced Studies , Nanyang Technological University , 637616 , Singapore
| | - I Levchenko
- Plasma Sources and Application Center/Space Propulsion Centre Singapore, NIE, and Institute of Advanced Studies , Nanyang Technological University , 637616 , Singapore
| | - K Bazaka
- Plasma Sources and Application Center/Space Propulsion Centre Singapore, NIE, and Institute of Advanced Studies , Nanyang Technological University , 637616 , Singapore
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34
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Levchenko I, Xu S, Mazouffre S, Keidar M, Bazaka K. Mars Colonization: Beyond Getting There. GLOBAL CHALLENGES (HOBOKEN, NJ) 2019; 3:1800062. [PMID: 31565356 PMCID: PMC6383964 DOI: 10.1002/gch2.201800062] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Revised: 08/20/2018] [Indexed: 06/09/2023]
Abstract
Colonization of Mars: As humans gradually overcome technological challenges of deep space missions, the possibility of exploration and colonization of extraterrestrial outposts is being seriously considered by space agencies and commercial entities alike. But should we do it just because we potentially can? Is such an undoubtedly risky adventure justified from the economic, legal, and ethical points of view? And even if it is, do we have a system of instruments necessary to effectively and fairly manage these aspects of colonization? In this essay, a rich diversity of current opinions on the pros and cons of Mars colonization voiced by space enthusiasts with backgrounds in space technology, economics, and materials science are examined.
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Affiliation(s)
- Igor Levchenko
- Plasma Sources and Applications Centre/Space Propulsion CentreNIENanyang Technological UniversitySingapore637616Singapore
- School of ChemistryPhysics and Mechanical EngineeringQueensland University of TechnologyBrisbaneQLD4000Australia
| | - Shuyan Xu
- Plasma Sources and Applications Centre/Space Propulsion CentreNIENanyang Technological UniversitySingapore637616Singapore
| | - Stéphane Mazouffre
- CNRSICAREElectric Propulsion Team1c Avenue de la Recherche Scientifique45071OrléansFrance
| | - Michael Keidar
- Mechanical and Aerospace EngineeringGeorge Washington UniversityWashingtonDC20052USA
| | - Kateryna Bazaka
- School of ChemistryPhysics and Mechanical EngineeringQueensland University of TechnologyBrisbaneQLD4000Australia
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35
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Margaryan N, Kokanyan N, Kokanyan E. Low-temperature synthesis and characteristics of fractal graphene layers. JOURNAL OF SAUDI CHEMICAL SOCIETY 2019. [DOI: 10.1016/j.jscs.2018.03.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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36
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Levchenko I, Bazaka K, Belmonte T, Keidar M, Xu S. Advanced Materials for Next-Generation Spacecraft. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2018; 30:e1802201. [PMID: 30302826 DOI: 10.1002/adma.201802201] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2018] [Revised: 07/16/2018] [Indexed: 06/08/2023]
Abstract
Spacecraft are expected to traverse enormous distances over long periods of time without an opportunity for maintenance, re-fueling, or repair, and, for interplanetary probes, no on-board crew to actively control the spacecraft configuration or flight path. Nevertheless, space technology has reached the stage when mining of space resources, space travel, and even colonization of other celestial bodies such as Mars and the Moon are being seriously considered. These ambitious aims call for spacecraft capable of self-controlled, self-adapting, and self-healing behavior. It is a tough challenge to address using traditional materials and approaches for their assembly. True interplanetary advances may only be attained using novel self-assembled and self-healing materials, which would allow for realization of next-generation spacecraft, where the concepts of adaptation and healing are at the core of every level of spacecraft design. Herein, recent achievements are captured and future directions in materials-driven development of space technology outlined.
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Affiliation(s)
- Igor Levchenko
- Plasma Sources and Applications Centre, NIE, Nanyang Technological University, Singapore, 637616, Singapore
- School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Kateryna Bazaka
- School of Chemistry, Physics and Mechanical Engineering, Queensland University of Technology, Brisbane, QLD, 4000, Australia
| | - Thierry Belmonte
- Department of Chemistry and Physics of Solids and Surfaces, Institut Jean Lamour - CNRS - University Lorraine, 2 allée André Guinier, Campus Artem, 54000, Nancy, France
| | - Michael Keidar
- Mechanical and Aerospace Engineering, George Washington University, Washington, DC, 20052, USA
| | - Shuyan Xu
- Plasma Sources and Applications Centre, NIE, Nanyang Technological University, Singapore, 637616, Singapore
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A Single-Use Microthruster Concept for Small Satellite Attitude Control in Formation-Flying Applications. AEROSPACE 2018. [DOI: 10.3390/aerospace5040119] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In recent years, the maturation of small satellite technology has led to their adoption for a variety of space missions. The next generation of small satellite missions, however, will likely have the satellites operating in formations or “constellations” to perform missions that are not currently possible. A key enabling technology for constellation-based missions is a miniaturized propulsion system that is capable of delivering the extremely low impulse levels required for maintaining precise relative position and orientation. Existing propulsion solutions for this regime suffer from compromises on power, safety, and cost that have limited their adoption. In this work, we describe a new, low-power micropropulsion concept based on the thermal decomposition of an inert chemical blowing agent (CBA) as the propellant. A meso-scale prototype device is designed, fabricated, and tested. The experimental results indicate that this concept, when appropriately scaled, is capable of providing thrust levels (∼1 μ N) and impulse-bits (∼0.1 μ N·s) that are commensurate with the intended application.
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Bazaka K, Baranov O, Cvelbar U, Podgornik B, Wang Y, Huang S, Xu L, Lim JWM, Levchenko I, Xu S. Oxygen plasmas: a sharp chisel and handy trowel for nanofabrication. NANOSCALE 2018; 10:17494-17511. [PMID: 30226508 DOI: 10.1039/c8nr06502k] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Although extremely chemically reactive, oxygen plasmas feature certain properties that make them attractive not only for material removal via etching and sputtering, but also for driving and sustaining nucleation and growth of various nanostructures in plasma bulk and on plasma-exposed surfaces. In this minireview, a number of representative examples is used to demonstrate key mechanisms and unique capabilities of oxygen plasmas and how these can be used in present-day nano-fabrication. In addition to modification and functionalisation processes typical for oxygen plasmas, their ability to catalyse the growth of complex nanoarchitectures is emphasized. Two types of technologies based on oxygen plasmas, namely surface treatment without a change in the size and shape of surface features, as well as direct growth of oxide structures, are used to better illustrate the capabilities of oxygen plasmas as a powerful process environment. Future applications and possible challenges for the use of oxygen plasmas in nanofabrication are discussed.
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Affiliation(s)
- K Bazaka
- School of Chemistry, Physics, Mechanical Engineering, Queensland University of Technology, Brisbane, Queensland 4000, Australia.
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Baranov O, Xu S, Ostrikov K, Wang BB, Cvelbar U, Bazaka K, Levchenko I. Towards universal plasma-enabled platform for the advanced nanofabrication: plasma physics level approach. ACTA ACUST UNITED AC 2018. [DOI: 10.1007/s41614-018-0016-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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