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Fu M, Critchley K. Inkjet printing of heavy-metal-free quantum dots-based devices: a review. NANOTECHNOLOGY 2024; 35:302002. [PMID: 38640903 DOI: 10.1088/1361-6528/ad40b3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/04/2023] [Accepted: 04/19/2024] [Indexed: 04/21/2024]
Abstract
Inkjet printing (IJP) has become a versatile, cost-effective technology for fabricating organic and hybrid electronic devices. Heavy-metal-based quantum dots (HM QDs) play a significant role in these inkjet-printed devices due to their excellent optoelectrical properties. Despite their utility, the intrinsic toxicity of HM QDs limits their applications in commercial products. To address this limitation, developing alternative HM-free quantum dots (HMF QDs) that have equivalent optoelectronic properties to HM QD is a promising approach to reduce toxicity and environmental impact. This article comprehensively reviews HMF QD-based devices fabricated using IJP methods. The discussion includes the basics of IJP technology, the formulation of printable HMF QD inks, and solutions to the coffee ring effect. Additionally, this review briefly explores the performance of typical state-of-the-art HMF QDs and cutting-edge characterization techniques for QD inks and printed QD films. The performance of printed devices based on HMF QDs is discussed and compared with those fabricated by other techniques. In the conclusion, the persisting challenges are identified, and perspectives on potential avenues for further progress in this rapidly developing research field are provided.
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Affiliation(s)
- Min Fu
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Kevin Critchley
- School of Physics and Astronomy, University of Leeds, Leeds, LS2 9JT, United Kingdom
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2
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Chen L, Zhang S, Duan Y, Song X, Chang M, Feng W, Chen Y. Silicon-containing nanomedicine and biomaterials: materials chemistry, multi-dimensional design, and biomedical application. Chem Soc Rev 2024; 53:1167-1315. [PMID: 38168612 DOI: 10.1039/d1cs01022k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
The invention of silica-based bioactive glass in the late 1960s has sparked significant interest in exploring a wide range of silicon-containing biomaterials from the macroscale to the nanoscale. Over the past few decades, these biomaterials have been extensively explored for their potential in diverse biomedical applications, considering their remarkable bioactivity, excellent biocompatibility, facile surface functionalization, controllable synthesis, etc. However, to expedite the clinical translation and the unexpected utilization of silicon-composed nanomedicine and biomaterials, it is highly desirable to achieve a thorough comprehension of their characteristics and biological effects from an overall perspective. In this review, we provide a comprehensive discussion on the state-of-the-art progress of silicon-composed biomaterials, including their classification, characteristics, fabrication methods, and versatile biomedical applications. Additionally, we highlight the multi-dimensional design of both pure and hybrid silicon-composed nanomedicine and biomaterials and their intrinsic biological effects and interactions with biological systems. Their extensive biomedical applications span from drug delivery and bioimaging to therapeutic interventions and regenerative medicine, showcasing the significance of their rational design and fabrication to meet specific requirements and optimize their theranostic performance. Additionally, we offer insights into the future prospects and potential challenges regarding silicon-composed nanomedicine and biomaterials. By shedding light on these exciting research advances, we aspire to foster further progress in the biomedical field and drive the development of innovative silicon-composed nanomedicine and biomaterials with transformative applications in biomedicine.
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Affiliation(s)
- Liang Chen
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
| | - Shanshan Zhang
- Department of Ultrasound Ruijin Hospital, Shanghai Jiaotong University School of Medicine, Shanghai 200025, P. R. China
| | - Yanqiu Duan
- Laboratory Center, Shanghai Municipal Hospital of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 200071, P. R. China.
| | - Xinran Song
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
| | - Meiqi Chang
- Laboratory Center, Shanghai Municipal Hospital of Traditional Chinese Medicine, Shanghai University of Traditional Chinese Medicine, Shanghai, 200071, P. R. China.
| | - Wei Feng
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
| | - Yu Chen
- Materdicine Lab, School of Life Sciences, Shanghai University, Shanghai, 200444, P. R. China.
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3
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Ueda H, Saitow KI. Cost-Effective Ultrabright Silicon Quantum Dots and Highly Efficient LEDs from Low-Carbon Hydrogen Silsesquioxane Polymers. ACS APPLIED MATERIALS & INTERFACES 2024; 16:985-997. [PMID: 38153210 DOI: 10.1021/acsami.3c11120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2023]
Abstract
Cost-effective methods of synthesizing bright colloidal silicon quantum dots (SiQDs) for use as heavy-metal-free QDs, which have applications as light sources in biomedicine and displays, are required. We report simple protocols for synthesizing ultrabright colloidal SiQDs and fabricating SiQD LEDs based on hydrogen silsesquioxane (HSQ) polymer synthesis. Red photoluminescence with a quantum yield (PLQY) of 60-80% and LEDs with an external quantum efficiency (EQE) of >10% were obtained at 1/3600th of the cost of existing methods. This was achieved by using HSiCl3 and a low-polarity solvent to prepare the HSQ polymer and by optimizing the LED hole-injection layer thickness. A stochastic analysis of 31 SiQD syntheses revealed that SiQDs with the highest PLQYs were obtained from a hard, low-carbon HSQ polymer precursor containing many Si-H groups and cage structures. Notably, simple FTIR measurements predicted whether a HSQ polymer would yield high-PLQY SiQDs and high-EQE LEDs. These straightforward, cost-effective protocols should lead to advances in SiQD synthesis and LED fabrication methods.
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Affiliation(s)
- Honoka Ueda
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Ken-Ichi Saitow
- Department of Chemistry, Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
- Department of Materials Science, Natural Science Center for Basic Research and Development (N-BARD), Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
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4
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Fluorescence and Nonlinear Optical Response of Graphene Quantum Dots Produced by Pulsed Laser Irradiation in Toluene. Molecules 2022; 27:molecules27227988. [PMID: 36432087 PMCID: PMC9694969 DOI: 10.3390/molecules27227988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 11/13/2022] [Accepted: 11/15/2022] [Indexed: 11/19/2022] Open
Abstract
Graphene quantum dots (GQDs), the zero dimensional (0D) single nanostructures, have many exciting technological applications in diversified fields such as sensors, light emitting devices, bio imaging probes, solar cells, etc. They are emerging as a functional tool to modulate light by means of molecular engineering due to its merits, including relatively low extend of loss, large outstretch of spatial confinement and control via doping, size and shape. In this article, we present a one pot, facile and ecofriendly synthesis approach for fabricating GQDs via pulsed laser irradiation of an organic solvent (toluene) without any catalyst. It is a promising synthesis choice to prepare GQDs due to its fast production, lack of byproducts and further purification, as well as the control over the product by accurate tuning of laser parameters. In this work, the second (532 nm) and third harmonic (355 nm) wavelengths of a pulsed nanosecond Nd:YAG laser have been employed for the synthesis. It has been found that the obtained GQDs display fluorescence and is expected to have potential applications in optoelectronics and light-harvesting devices. In addition, nonlinear optical absorption of the prepared GQDs was measured using the open aperture z-scan technique (in the nanosecond regime). These GQDs exhibit excellent optical limiting properties, especially those synthesized at 532 nm wavelength.
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5
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Ono T, Xu Y, Sakata T, Saitow KI. Designing Efficient Si Quantum Dots and LEDs by Quantifying Ligand Effects. ACS APPLIED MATERIALS & INTERFACES 2022; 14:1373-1388. [PMID: 34967610 DOI: 10.1021/acsami.1c18779] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The impact of colloidal silicon quantum dots (SiQDs) on next-generation light sources is promising. However, factors determining the efficiency of SiQDs, such as the photoluminescence (PL) wavelength, PL quantum yield (PLQY), and the SiQD LED performance based on the type of ligand, ligand coverage, stress, and dangling bonds, have not been quantified. Characterizing these variables would accelerate the design and implementation of SiQDs. Herein, colloidal SiQDs were synthesized by pyrolyzing hydrogen silsesquioxane and their surfaces were terminated with 1-decene by either thermal hydrosilylation (HT-SiQDs) or room-temperature hydrosilylation using PCl5 (RT-SiQD). As a result, PL, PL-excitation, and ultraviolet-visible absorption spectra were similar, but their PLQYs were significantly different: 54% (RT-SiQDs) vs 19% (HT-SiQDs). To understand their similarities and differences, surface coverages (dangling bonds, Si-H (≡Si-H1, ═Si-H2, and -Si-H3), Si-O-Si, Si-C, Si-Cl) were determined. A core stress analysis established that a single ligand terminated to a SiQD bond site stretched the Si-Si bond length by 0.3%. From the two well-defined SiQDs, the PLQY and SiQD LED efficiency were attributed to four factors: low coverage of insulator ligands, the Cl ligand effect on radiative and nonradiative rates, negligible dangling bonds, and a SiQD core with low tensile stress. The PLQY of the RT-SiQDs in toluene was 80%. In addition, the 20× electroluminescence intensity difference of the LEDs originated from a 10× difference in current density and a 2× difference in Auger recombination. The concepts demonstrated here can be applied to further improve the PLQY and LED efficiencies of SiQDs with other ligands.
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Affiliation(s)
- Taisei Ono
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Yuping Xu
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Toshiki Sakata
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Ken-Ichi Saitow
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
- Natural Science Center for Basic Research and Development (N-BARD), Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
- Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
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6
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Sakamoto M, Terada S, Mizutani T, Saitow KI. Large Field Enhancement of Nanocoral Structures on Porous Si Synthesized from Rice Husks. ACS APPLIED MATERIALS & INTERFACES 2021; 13:1105-1113. [PMID: 33332080 DOI: 10.1021/acsami.0c14248] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Silicon (Si) is a highly abundant, environmentally benign, and durable material and is the most popular semiconductor material; and it is used for the field enhancement of dielectric materials. Porous Si (PSi) exhibits high functionality due to its specific structure. However, the field enhancement of PSi has not been clarified sufficiently. Herein, we present the field enhancement of PSi by the fluorescence intensity enhancement of a dye molecule. The raw material used for producing PSi was rice husk, a biomass material. A nanocoral structure, consisting of spheroidal structures on the surface of PSi, was observed when PSi was subjected to chemical processes and pulsed laser melting, and it demonstrated large field enhancement with an enhancement factor (EF) of up to 545. Confocal microscopy was used for EF mapping of samples before and after laser melting, and the maps were superimposed on nanoscale scanning electron microscope images to highlight the EF effect as a function of microstructure. Nanocoral Si with high EF values were also evaluated by analyzing the porosity from gas adsorption measurements. Nanocoral Si was responsible for the high EF, according to thermodynamic calculations and agreement between experimental and calculation results as determined by Mie scattering theory.
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Affiliation(s)
- Masanori Sakamoto
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Shiho Terada
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Tomoya Mizutani
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
| | - Ken-Ichi Saitow
- Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
- Natural Science Center for Basic Research and Development (N-BARD), Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
- Graduate School of Advanced Science and Engineering, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8526, Japan
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7
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Morozova S, Alikina M, Vinogradov A, Pagliaro M. Silicon Quantum Dots: Synthesis, Encapsulation, and Application in Light-Emitting Diodes. Front Chem 2020; 8:191. [PMID: 32318540 PMCID: PMC7154098 DOI: 10.3389/fchem.2020.00191] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2019] [Accepted: 03/02/2020] [Indexed: 12/29/2022] Open
Abstract
Silicon quantum dots (SiQDs) are semiconductor Si nanoparticles ranging from 1 to 10 nm that hold great applicative potential as optoelectronic devices and fluorescent bio-marking agents due to their ability to fluoresce blue and red light. Their biocompatibility compared to conventional toxic Group II-VI and III-V metal-based quantum dots makes their practical utilization even more attractive to prevent environmental pollution and harm to living organisms. This work focuses on their possible use for light-emitting diode (LED) manufacturing. Summarizing the main achievements over the past few years concerning different Si quantum dot synthetic methods, LED formation and characteristics, and strategies for their stabilization by microencapsulation and modification of their surface by specific ligands, this work aims to provide guidance en route to the development of the first stable Si-based light-emitting diodes.
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Affiliation(s)
- Sofia Morozova
- Laboratory of Inkjet Printing of Functional Materials, SCAMT Institute, ITMO University, Saint-Petersburg, Russia
| | - Mariya Alikina
- Laboratory of Inkjet Printing of Functional Materials, SCAMT Institute, ITMO University, Saint-Petersburg, Russia
| | - Aleksandr Vinogradov
- Laboratory of Inkjet Printing of Functional Materials, SCAMT Institute, ITMO University, Saint-Petersburg, Russia
| | - Mario Pagliaro
- Istituto per lo Studio dei Materiali Nanostrutturati, CNR, Palermo, Italy
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8
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Tang J, Sakamoto M, Ohta H, Saitow KI. 1% defect enriches MoS 2 quantum dot: catalysis and blue luminescence. NANOSCALE 2020; 12:4352-4358. [PMID: 31808769 DOI: 10.1039/c9nr07612c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Defects in solids are typically recognized as unfavorable, leading to degradation of the structure and properties of the material. However, defects occasionally provide extraordinary benefits as the active sites of catalysts and chemical reactions, and can result in the creation of new electronic states. In particular, a low-dimensional material can become a defect-rich material due to the unique ratio of surface area to volume, giving many dangling bonds. Herein, we report the rapid (20 min) synthesis of MoS2 quantum dots (QDs) with a diameter of 4 nm at room temperature using nanosecond pulsed laser ablation in a binary solvent. The MoS2 QDs are crystalline particles composed of 3-5 layers and contain sulfur vacancies at an atomic concentration of 1% acting as a functional defect. The MoS2 QDs exhibit excellent electrocatalytic performance (Tafel slope = 49 mV dec-1) for the hydrogen evolution reaction and high quantum yield blue photoluminescence with a large Stokes shift.
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Affiliation(s)
- Jingmin Tang
- Department of chemistry, Graduate school of science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526, Japan.
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9
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Saitow KI, Okamoto Y, Suemori H. Size-Selected Submicron Gold Spheres: Controlled Assembly onto Metal, Carbon, and Plastic Substrates. ACS OMEGA 2019; 4:14307-14311. [PMID: 31508555 PMCID: PMC6733168 DOI: 10.1021/acsomega.9b01999] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2019] [Accepted: 08/02/2019] [Indexed: 06/10/2023]
Abstract
Size-selected submicron spheres become very useful building blocks if the spheres could be synthesized and integrated at any desired position. In particular, spheres having a similar size to visible-light wavelength have attracted much attention. Here, we show the synthesis and assembly of size-selected submicron gold spheres using pulsed laser ablation of a gold plate in a supercritical fluid. Four findings were obtained in the study. Submicron spheres with a narrow size distribution were generated, and the polydispersity was ≈ 6%. The average diameter was controlled from 600 to 1000 nm. A thermodynamic condition for scalable synthesis was found. The assembly of spheres onto a metal, carbon, or plastic substrate was accomplished.
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Affiliation(s)
- Ken-Ichi Saitow
- Natural Science Center for Basic Research and Development (N-BARD), and Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-hiroshima 739-8526, Japan
| | - Yoshinori Okamoto
- Natural Science Center for Basic Research and Development (N-BARD), and Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-hiroshima 739-8526, Japan
| | - Hidemi Suemori
- Natural Science Center for Basic Research and Development (N-BARD), and Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-hiroshima 739-8526, Japan
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10
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Xin Y, Xu Y, Lee J, Shirai T. A novel and facile synthesis of visible photoluminescence Si nanocrystals by room temperature mechanochemical disproportionation of SiO. RSC Adv 2019; 9:8310-8314. [PMID: 35518703 PMCID: PMC9061880 DOI: 10.1039/c9ra00195f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 02/26/2019] [Indexed: 11/25/2022] Open
Abstract
Visible photoluminescence Si nanocrystals (Si NCs) are synthesized via a novel and facile room temperature mechanochemical disproportionation of SiO.![]()
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Affiliation(s)
- Yunzi Xin
- Advanced Ceramics Research Center, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya Aichi 466-8555 Japan
| | - Yuping Xu
- Advanced Ceramics Research Center, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya Aichi 466-8555 Japan
| | - Jeongbin Lee
- Advanced Ceramics Research Center, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya Aichi 466-8555 Japan
| | - Takashi Shirai
- Advanced Ceramics Research Center, Nagoya Institute of Technology Gokiso-cho, Showa-ku Nagoya Aichi 466-8555 Japan
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11
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Wang J, Zhang Y, Hao H, Shen W. Structural evolution and effective improvement of emission quantum yields for silicon nanocrystals synthesized by femtosecond laser ablation in HF-contained solution. NANOTECHNOLOGY 2019; 30:015705. [PMID: 30362465 DOI: 10.1088/1361-6528/aae67c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Stable luminescent colloidal silicon (Si) nanocrystals (NCs) with sufficient surface protection are prepared through femtosecond laser ablation in organic solvent containing diverse concentrations of HF solution. The average size of Si NCs shows the decreasing tendency from 6.5 to 2.7 nm when the concentration of HF varies from 0 to 11.1 vol% (volume ratio). In line with the structural evolution, UV-visible absorption, photoluminescence (PL) excitation spectra, and time-resolved PL, we propose that room temperature blue emission peaks at 412 and 440 nm originate from alkyl-related radiative recombination centers. The enhanced PL quantum yield of colloidal Si NCs from 16.3% to 76.5% has been attributed to the effective passivation and suppression of non-radiative defect centers with increasing HF concentration from 0 to 11.1 vol%.
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Affiliation(s)
- Jianjun Wang
- College of Material Engineering, Shanghai University of Engineering Science, 333 Long Teng Road, Shanghai 201620, People's Republic of China
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12
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Zhang YX, Wu WS, Hao HL, Shen WZ. Femtosecond laser-induced size reduction and emission quantum yield enhancement of colloidal silicon nanocrystals: effect of laser ablation time. NANOTECHNOLOGY 2018; 29:365706. [PMID: 29916813 DOI: 10.1088/1361-6528/aacd75] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Colloidal silicon (Si) nanocrystals (NCs) with different sizes were successfully prepared by femtosecond laser ablation under different laser ablation time (LAT). The mean size decreases from 4.23 to 1.42 nm by increasing the LAT from 30 to 120 min. In combination with structural characterization, temperature-dependent photoluminescence (PL), time-resolved PL and PL excitation spectra, we attribute room-temperature blue emissions peaked at 405 and 430 nm to the radiative recombination of electron-hole pairs via the oxygen-deficient centers related to Si-C-H2 and Si-O-Si bonds of colloidal Si NCs prepared in 1-octene, respectively. In particular, the measured PL quantum yield of colloidal Si NCs has been enhanced significantly from 23.6% to 55.8% by prolonging the LAT from 30 to 120 min.
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Affiliation(s)
- Y X Zhang
- College of Material Engineering, Shanghai University of Engineering Science, 333 Long Teng Road, Shanghai 201620, People's Republic of China
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13
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Kocevski V. Temperature dependence of radiative lifetimes, optical and electronic properties of silicon nanocrystals capped with various organic ligands. J Chem Phys 2018; 149:054301. [DOI: 10.1063/1.5039281] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Affiliation(s)
- V. Kocevski
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, S-751 20 Uppsala, Sweden
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14
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Kajiya D, Saitow KI. Si nanocrystal solution with stability for one year. RSC Adv 2018; 8:41299-41307. [PMID: 35559330 PMCID: PMC9091691 DOI: 10.1039/c8ra08816k] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Accepted: 12/03/2018] [Indexed: 12/14/2022] Open
Abstract
Colloidal silicon nanocrystals (SiNCs) are a promising material for next-generation nanostructured devices. High-stability SiNC solutions are required for practical use as well as studies on the properties of SiNC. Here, we show a solution of SiNCs that was stable for one year without aggregation. The stable solution was synthesized by a facile process, i.e., pulsed laser ablation of a Si wafer in isopropyl alcohol (IPA). The long-term stability was due to a large ζ-potential of −50 mV from a SiNC passivation layer composed of oxygen, hydrogen, and alkane groups, according to the results of eight experiments and theoretical calculations. This passivation layer also resulted in good performance as an additive for a conductive polymer film. Namely, a 5-fold enhancement in carrier density was established by the addition of SiNCs into an organic conductive polymer, poly(3-dodecylthiophene), which is useful for solar cells. Furthermore, it was found that fresh (<1 day) and aged (4 months) SiNCs give the same enhancement. The long-term stability was attributed to a great repulsive energy in IPA, whose value was quantified as a function the distance between SiNCs. A stable nanocrystal for one year without aggregation in a liquid is synthesized by one-step, one-pot, and one-hour process.![]()
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Affiliation(s)
- Daisuke Kajiya
- Natural Science Center for Basic Research and Development (N-BARD)
- Hiroshima University
- Higashi-hiroshima
- Japan
- Department of Chemistry
| | - Ken-ichi Saitow
- Natural Science Center for Basic Research and Development (N-BARD)
- Hiroshima University
- Higashi-hiroshima
- Japan
- Department of Chemistry
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15
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Gökce B, Amendola V, Barcikowski S. Opportunities and Challenges for Laser Synthesis of Colloids. Chemphyschem 2017; 18:983-985. [DOI: 10.1002/cphc.201700310] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2017] [Indexed: 11/06/2022]
Affiliation(s)
- Bilal Gökce
- University of Duisburg-Essen; Technical Chemistry I; Universitaetsstrasse 7 45141 Essen Germany
| | - Vincenzo Amendola
- University of Padova; Department of Chemical Sciences; Via Marzolo 1 35131 Padova Italy
| | - Stephan Barcikowski
- University of Duisburg-Essen; Technical Chemistry I; Universitaetsstrasse 7 45141 Essen Germany
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