1
|
Kathiravan P, Thillaivelavan K, Viruthagiri G. Influence of Cu-ion doping in NiO NPs and their structural, morphological, optical and magnetic behaviors for optoelectronic devices and magnetic applications. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2024; 308:123745. [PMID: 38104428 DOI: 10.1016/j.saa.2023.123745] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/12/2023] [Revised: 12/06/2023] [Accepted: 12/07/2023] [Indexed: 12/19/2023]
Abstract
NiO and Cu-ion doped NiO nanoparticles with various concentrations (0.01-0.04 M) have been effectively synthesized in the current investigation using chemical precipitation method. The following techniques were used to characterized the materials' structural, morphological, elemental analysis, functional group, optical and magnetic properties: XRD, TEM, HR-TEM, SAED, SEM, EDX, FTIR, UV, PL and VSM. According to this Scherrer formula, the average crystalline sizes of the materials of pure NiO and Cu-doped NiO were determined to be 16.37 nm, 15.21 nm, 14.88 nm, 18.35 nm, and 10.88 nm, respectively. The HR-TEM images revealed that the d-spacing values about 0.24 nm, which coincides with the (111) plane of cubic NiO for pure and copper doped NiO nanoparticles. The SEM micrographs of Cu-doped NiO nanomaterials shows tiny agglomerated particles, while that of pure NiO nanoparticles shows spherical structure. Pure NiO and Cu-doped NiO nanoparticles have band gap values of 2.32 eV, 2.29 eV, 2.24 eV, 2.22 eV, and 2.27 eV, respectively. The Cu-doped NiO nanoparticles (0.01-0.03 M) at various concentrations can significantly reduce the band gap without significantly altering the structure, making them a potential material for creating optoelectronic devices. Copper was incorporated into NiO nanoparticles, which had a significant impact on the magnetic properties and changed the material from weakly ferromagnetic to ferromagnetic. In comparison to undoped NiO nanoparticles, the saturation magnetization and coercivity values of the 0.01 M and 0.03 M of Cu-doped nanoparticles is much higher. This outcome demonstrates that such Cu-doped NiO nanoparticles have promising magnetic applications.
Collapse
Affiliation(s)
- P Kathiravan
- Department of Physics, Periyar Arts College, Cuddalore 607 001, Tamil Nadu, India
| | - K Thillaivelavan
- Department of Physics, Periyar Arts College, Cuddalore 607 001, Tamil Nadu, India.
| | - G Viruthagiri
- Department of Physics, Annamalai University, Annamalai Nagar, Chidambaram 608 002, Tamil Nadu, India
| |
Collapse
|
2
|
Ramos-Justicia JF, Urbieta A, Fernández P. Rapid Growth of Metal-Metal Oxide Core-Shell Structures through Joule Resistive Heating: Morphological, Structural, and Luminescence Characterization. MATERIALS (BASEL, SWITZERLAND) 2023; 17:208. [PMID: 38204061 PMCID: PMC10780081 DOI: 10.3390/ma17010208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2023] [Revised: 12/14/2023] [Accepted: 12/28/2023] [Indexed: 01/12/2024]
Abstract
The aim of this study is to prove that resistive heating enables the synthesis of metal/metal oxide composites in the form of core-shell structures. The thickness and morphology of the oxide layer depends strongly on the nature of the metal, but the influences of parameters such as the time and current profiles and the presence of an external field have also been investigated. The systems chosen for the present study are Zn/ZnO, Ti/TiO2, and Ni/NiO. The characterization of the samples was performed using techniques based on scanning electron microscopy (SEM). The thicknesses of the oxide layers varied from 10 μm (Zn/ZnO) to 50 μm (Ni/NiO). In the case of Zn- and Ti-based composites, the growth of nanostructures on the oxide layer was observed. Micro- and nanoneedles formed on the ZnO layer while prism-like structures appeared on the TiO2. In the case of the NiO layer, micro- and nanocrystals were observed. Applying an external electric field seemed to align the ZnO needles, whereas its effect on TiO2 and NiO was less appreciable, principally affecting the shape of their grain boundaries. The chemical compositions were analysed using X-ray spectroscopy (EDX), which confirmed the existence of an oxide layer. Structural information was obtained by means of X-ray diffraction (XRD) and was later checked using Raman spectroscopy. The oxide layers seemed to be crystalline and, although some non-stoichiometric phases appeared, the stoichiometric phases were predominant; these were wurtzite, rutile, and cubic for Zn, Ti, and Ni oxides, respectively. The photoluminescence technique was used to study the distribution of defects on the shell, and mainly visible bands (2-2.5 eV), attributed to oxygen vacancies, were present. The near-band edges of ZnO and TiO2 were also observed around 3.2-3.3 eV.
Collapse
Affiliation(s)
| | | | - Paloma Fernández
- Department of Materials Physics, Faculty of Physics, Complutense University of Madrid, 28040 Madrid, Spain; (J.F.R.-J.); (A.U.)
| |
Collapse
|
3
|
A/P Chowmasundaram Y, Tan TL, Nulit R, Jusoh M, Rashid SA. Recent developments, applications and challenges for carbon quantum dots as a photosynthesis enhancer in agriculture. RSC Adv 2023; 13:25093-25117. [PMID: 37622012 PMCID: PMC10445218 DOI: 10.1039/d3ra01217d] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2023] [Accepted: 08/15/2023] [Indexed: 08/26/2023] Open
Abstract
Since the world's population is expanding, mankind may be faced with a huge dilemma in the future, which is food scarcity. The situation can be mitigated by employing sustainable cutting-edge agricultural methods to maintain the food supply chain. In recent years, carbon quantum dots (CQD), a member of the well-known carbon-based nanomaterials family, have given rise to a new generation of technologies that have the potential to revolutionise horticulture and agriculture research. CQD has drawn much attention from the research community in agriculture owing to their remarkable properties such as good photoluminescence behaviour, high biocompatibility, photo-induced electron transfer, low cost, and low toxicity. These unique properties have led CQD to become a promising material to increase plant growth and yield in the agriculture field. This review paper highlights the recent advances of CQD application in plant growth and photosynthesis rate at different concentrations, with a focus on CQD uptake and translocation, as well as electron transfer mechanism. The toxicity and biocompatibility studies of CQD, as well as industrial scale applications of CQD for agriculture are discussed. Finally, the current challenges of the present and future perspectives in this agriculture research are presented.
Collapse
Affiliation(s)
- Yamuna A/P Chowmasundaram
- Institute of Nanoscience and Nanotechnology, Universiti Putra Malaysia 43400 UPM Serdang Selangor Malaysia
| | - Tong Ling Tan
- Institute of Nanoscience and Nanotechnology, Universiti Putra Malaysia 43400 UPM Serdang Selangor Malaysia
| | - Rosimah Nulit
- Department of Biology, Faculty Science, Universiti Putra Malaysia 43400 UPM Serdang Selangor Malaysia
| | - Mashitah Jusoh
- Department of Crop Science, Faculty of Agriculture, Universiti Putra Malaysia 43400 Selangor Malaysia
| | - Suraya Abdul Rashid
- Institute of Nanoscience and Nanotechnology, Universiti Putra Malaysia 43400 UPM Serdang Selangor Malaysia
- Department of Chemical and Environmental Engineering, Faculty of Engineering, Universiti Putra Malaysia 43400 UPM Serdang Selangor Malaysia
| |
Collapse
|
4
|
Al-Mushki AAA, Ahmed AAA, Abdulwahab AM, Qaid SAS, Alzayed NS, Shahabuddin M, Abduljalil JMA, Saad FAA. Effect of the molar ratio of (Ni 2+ and Fe 3+) on the magnetic, optical and antibacterial properties of ternary metal oxide CdO-NiO-Fe 2O 3 nanocomposites. Sci Rep 2023; 13:9021. [PMID: 37270550 DOI: 10.1038/s41598-023-36262-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 05/31/2023] [Indexed: 06/05/2023] Open
Abstract
In this work, the effect of the molar ratio of (Ni2+ and Fe3+) on the properties of CdO-NiO-Fe2O3 nanocomposites was investigated. The synthesis of CdO-NiO-Fe2O3 nanocomposites was carried out by self-combustion. XRD, UV-Vis, PL and VSM were used to describe the physical properties of the materials. The results showed significant progress in structural and optical properties supporting antibacterial activity. For all samples, the particle size decreased from 28.96 to 24.95 nm with increasing Ni2+ content and decreasing Fe3+ content, as shown by the XRD pattern, which also shows the crystal structure of cubic CdO, cubic NiO, and cubic γ-Fe2O3 spinel. The Ni2+ and Fe3+ contents in the CdO-NiO-Fe2O3 nanocomposites have also been shown to enhance the ferromagnetic properties. Due to the significant coupling between Fe2O3 and NiO, the coercivity Hc values of the samples increase from 66.4 to 266 Oe. The potential of the nanocomposites for antibacterial activity was investigated against Gram-positive (Staphylococcus aureus) and Gram-negative (Pseudomonas aeruginosa, Escherichia coli, and Moraxella catarrhalis) bacteria. Comparison of P. aeruginosa with E. coli, S. aureus and M. catarrhalis showed that it has a stronger antibacterial activity with a ZOI of 25 mm.
Collapse
Affiliation(s)
- Asma A A Al-Mushki
- Department of Physics, Faculty of Applied Science, Thamar University, 87246, Dhamar, Yemen
| | - Abdullah A A Ahmed
- Department of Physics, Faculty of Applied Science, Thamar University, 87246, Dhamar, Yemen.
| | - A M Abdulwahab
- Department of Physics, Faculty of Applied Science, Thamar University, 87246, Dhamar, Yemen
| | - Salem A S Qaid
- Department of Physics, Faculty of Applied Science, Thamar University, 87246, Dhamar, Yemen
- Department of Physics and Astronomy, College of Science, King Saud University, PO Box 2455, Riyadh, 11451, Saudi Arabia
| | - Nasser S Alzayed
- Department of Physics and Astronomy, College of Science, King Saud University, PO Box 2455, Riyadh, 11451, Saudi Arabia
| | - Mohammed Shahabuddin
- Department of Physics and Astronomy, College of Science, King Saud University, PO Box 2455, Riyadh, 11451, Saudi Arabia
| | - Jameel M A Abduljalil
- Department of Biology, Faculty of Applied Science, Thamar University, 87246, Dhamar, Yemen
| | - Fuad A A Saad
- Department of Biology, Faculty of Applied Science, Thamar University, 87246, Dhamar, Yemen
| |
Collapse
|
5
|
Dejam L, Sabbaghzadeh J, Ghaderi A, Solaymani S, Matos RS, Țălu Ș, da Fonseca Filho HD, Sari AH, Kiani H, Shayegan AHS, Doudaran MA. Advanced nano-texture, optical bandgap, and Urbach energy analysis of NiO/Si heterojunctions. Sci Rep 2023; 13:6518. [PMID: 37085689 PMCID: PMC10121669 DOI: 10.1038/s41598-023-33713-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2022] [Accepted: 04/18/2023] [Indexed: 04/23/2023] Open
Abstract
Due to the large number of industrial applications of transparent conductive oxides (TCOs), this study focuses on one of the most important metal oxides. The RF-magnetron sputtering method was used to fabricate NiO thin films on both quartz and silicon substrates at room temperature under flow of Argon and Oxygen. The sputtered samples were annealed in N2 atmosphere at 400, 500, and 600 °C for 2 hours. Using the AFM micrographs and WSXM 4.0 software, the basic surface parameters, including root mean square roughness, average roughness, kurtosis, skewness, etc., were computed. Advanced surface parameters were obtained by the Shannon entropy through a developed algorithm, and the power spectral density and fractal succolarity were extracted by related methods. Optical properties were studied using a transmittance spectrum to achieve the optical bandgap, absorption coefficient, Urbach energy, and other optical parameters. Photoluminescence properties also showed interesting results in accordance with optical properties. Finally, electrical characterizations and I-V measurements of the NiO/Si heterojunction device demonstrated that it can be used as a good diode device.
Collapse
Affiliation(s)
- Laya Dejam
- Quantum Technologies Research Center (QTRC), Science and Research Branch, Islamic Azad University, Tehran, Iran
- Physics Department, West Tehran Branch, Islamic Azad University, Tehran, Iran
| | - Jamshid Sabbaghzadeh
- Quantum Technologies Research Center (QTRC), Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Atefeh Ghaderi
- Quantum Technologies Research Center (QTRC), Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Shahram Solaymani
- Quantum Technologies Research Center (QTRC), Science and Research Branch, Islamic Azad University, Tehran, Iran.
| | - Robert S Matos
- Amazonian Materials Group, Physics Department, Federal University of Amapá-UNIFAP, Macapá, Amapá, Brazil
| | - Ștefan Țălu
- The Directorate of Research, Development and Innovation Management (DMCDI), Technical University of Cluj-Napoca, Cluj-Napoca, Cluj County, Romania
| | - Henrique D da Fonseca Filho
- Laboratory of Synthesis of Nanomaterials and Nanoscopy, Physics Department, Federal University of Amazonas-UFAM, Manaus, Amazonas, Brazil
| | - Amir Hossein Sari
- Quantum Technologies Research Center (QTRC), Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Hanieh Kiani
- Physics Department, Science and Research Branch, Islamic Azad University, Tehran, Iran
| | - Amir Hossein Salehi Shayegan
- Quantum Technologies Research Center (QTRC), Science and Research Branch, Islamic Azad University, Tehran, Iran
- Mathematics Department, Faculty of Basic Science, Khatam-Ol-Anbia (PBU) University, Tehran, Iran
| | - Mahdi Astani Doudaran
- Quantum Technologies Research Center (QTRC), Science and Research Branch, Islamic Azad University, Tehran, Iran
| |
Collapse
|
6
|
Biogenic synthesis of nickel oxide nanoparticles using Averrhoa bilimbi and investigation of its antibacterial, antidiabetic and cytotoxic properties. INORG CHEM COMMUN 2022. [DOI: 10.1016/j.inoche.2022.109930] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
|
7
|
Ahmad R, Shah MA. Nickel oxide (NiO) nanoflakes prepared through hydrothermal method and integration into acetone gas sensing application. CHEMICAL PAPERS 2022. [DOI: 10.1007/s11696-022-02448-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
|
8
|
Synthesis and Investigation of Pure and Cu-Doped NiO Nanofilms for Future Applications in Wastewater Treatment Rejected by Textile Industry. Catalysts 2022. [DOI: 10.3390/catal12090931] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Pure and Cu-doped NiO films were synthesized via a soft chemical process. They were deposited on glass substrates heated to 400 °C. Different atomic percentage ratios (2, 4, 6, 8, and 10%) of Cu-doping were used. The prepared samples were characterized by several techniques such as X-ray diffraction for crystallographic study, SEM and AFM for microstructural and morphological properties, and UV-Visible spectroscopy for optical and photocatalytical analysis. XRD results of pure and Cu-doped NiO films indicated the formation of NiO polycrystalline phases under a cubic structure with a favored orientation along the (200) plane noticed in all sprayed films. SEM images revealed the formation of NiO nanoparticles of spherical forms whose sizes increase and agglomerate with increasing Cu-doping. At 10% Cu-doping, NiO agglomeration was extended to the whole surface. AFM images showed a textured and rough surface composed of NiO nanoparticles of average size varying from 16 to 10 nm depending on Cu-doping concentration. UV-visible spectroscopy confirmed the transparency of NiO films and their semiconducting character with a band gap ranging from 3.4450 eV to 2.8648 eV. The photocatalytical properties of pure and Cu-NiO films were enhanced by Cu-doping particles as revealed by the degradation of methylene blue (MB) solution subjected to irradiation.
Collapse
|
9
|
Sharma M, Kumar A, Krishnan V. Influence of oxygen vacancy defects on Aurivillius phase layered perovskite oxides of bismuth towards photocatalytic environmental remediation. NANOTECHNOLOGY 2022; 33:275702. [PMID: 35412470 DOI: 10.1088/1361-6528/ac6088] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2021] [Accepted: 03/23/2022] [Indexed: 06/14/2023]
Abstract
The low light absorption and rapid recombination of photogenerated charge carriers are primary contributors to the low activity of various photocatalysts. Fabrication of oxygen vacancy defect-rich materials for improved photocatalytic activities has been attracting tremendous attention from researchers all over the world. In this work, we have compared the photocatalytic activities of oxygen vacancy-rich Bi2MoO6(BMO-OV) and Bi2WO6(BWO-OV) for the degradation of a model pharmaceutical pollutant, ciprofloxacin under visible light irradiation. The photocatalytic activity was increased from 47% to 77% and 40% to-67% for BMO-OVand BWO-OV, respectively in comparison to pristine oxides. This enhancement can be ascribed to suppressed charge carrier recombination and increased surface active sites. In addition, scavenger studies have been done to explain the role of photoinduced charge carriers in the degradation mechanism. Moreover, oxygen vacancy-rich photocatalysts have remained stable even after three consecutive cycles, making them promising materials for practical applications. Overall, this work provides deeper insight into the design and development of oxygen vacancy-rich materials.
Collapse
Affiliation(s)
- Manisha Sharma
- School of Basic Sciences and Advanced Materials Research Center, Indian Institute of Technology Mandi, Mandi 175075, Himachal Pradesh, India
| | - Ashish Kumar
- School of Basic Sciences and Advanced Materials Research Center, Indian Institute of Technology Mandi, Mandi 175075, Himachal Pradesh, India
| | - Venkata Krishnan
- School of Basic Sciences and Advanced Materials Research Center, Indian Institute of Technology Mandi, Mandi 175075, Himachal Pradesh, India
| |
Collapse
|
10
|
NiO-Ni foam supported Ag3PO4 for efficient photoelectrocatalytic degradation of oil pollutant in water. Sep Purif Technol 2022. [DOI: 10.1016/j.seppur.2021.120410] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
11
|
Reddy B KS, Veeralingam S, Borse PH, Badhulika S. 1D NiO-3D Fe 2O 3mixed dimensional heterostructure for fast response flexible broadband photodetector. NANOTECHNOLOGY 2022; 33:235201. [PMID: 35203065 DOI: 10.1088/1361-6528/ac5838] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Accepted: 02/24/2022] [Indexed: 06/14/2023]
Abstract
Conventional heterojunction photodetectors rely on planar junction architecture which suffer from low interfacial contact area, inferior light absorption characteristics and complex fabrication schemes. Heterojunctions based on mixed dimensional nanostructures such as 0D-1D, 1D-2D, 1D-3D etc have recently garnered exceptional research interest owing to their atomically sharp interfaces, tunable junction properties such as enhanced light absorption cross-section. In this work, a flexible broadband UV-vis photodetector employing mixed dimensional heterostructure of 1D NiO nanofibers and 3D Fe2O3nanoparticles is fabricated. NiO nanofibers were synthesized via economical and scalable electro-spinning technique and made composite with Fe2O3nanoclusters for hetero-structure fabrication. The optical absorption spectra of NiO nanofibers and Fe2O3nanoparticles exhibit peak absorption in UV and visible spectra, respectively. The as-fabricated photodetector displays quick response times of 0.09 s and 0.18 s and responsivities of 5.7 mA W-1(0.03 mW cm-2) and 5.2 mA W-1(0.01 mW cm-2) for UV and visible spectra, respectively. The fabricated NiO-Fe2O3device also exhibits excellent detectivity in the order of 1012jones. The superior performance of the device is ascribed to the type-II heterojunction between NiO-Fe2O3nanostructures, which results in the localized built-in potential at their interface, that aids in the effective carrier separation and transportation. Further, the flexible photodetector displays excellent robustness when bent over ∼1000 cycles thereby proving its potential towards developing reliable, diverse functional opto-electronic devices.
Collapse
Affiliation(s)
- Kumaar Swamy Reddy B
- Department of Electrical Engineering, Indian Institute of Technology-Hyderabad, Kandi, Sangareddy, Hyderabad, India
- Centre for Nanomaterials, International Advanced Research Centre for Powder, Metallurgy & New Materials, Balapur, Hyderabad, India
| | - Sushmitha Veeralingam
- Department of Electrical Engineering, Indian Institute of Technology-Hyderabad, Kandi, Sangareddy, Hyderabad, India
| | - Pramod H Borse
- Centre for Nanomaterials, International Advanced Research Centre for Powder, Metallurgy & New Materials, Balapur, Hyderabad, India
| | - Sushmee Badhulika
- Department of Electrical Engineering, Indian Institute of Technology-Hyderabad, Kandi, Sangareddy, Hyderabad, India
| |
Collapse
|
12
|
Karthikeyan C, Sisubalan N, Varaprasad K, Aepuru R, Yallapu MM, Viswanathan MR, Umaralikhan, Sadiku R. Hybrid nanoparticles from chitosan and nickel for enhanced biocidal activities. NEW J CHEM 2022. [DOI: 10.1039/d2nj02009b] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Cs/Ni/NiO hybrid nanomaterials were prepared by using the precipitation method, The HNPs displayed a nanoflake-like structure and showed high biocidal activity against S. aureus and E. coli strains and breast cancer cell lines.
Collapse
Affiliation(s)
| | - Natarajan Sisubalan
- Department of Botany, Bishop Heber College (Autonomous), Affi. To Bharathidasan University, Trichy 620017, Tamil Nadu, India
| | - Kokkarachedu Varaprasad
- Facultad de Ingeniería, Arquitectura y Diseño, Universidad San Sebastián, Lientur 1457, Concepción 4080871, Chile
| | - Radhamanohar Aepuru
- Departamento de Ingeniería Mecánica, Facultad de Ingeniería, Universidad Tecnológica Metropolitana, Santiago, Chile
| | - Murali M. Yallapu
- Department of Immunology and Microbiology, School of Medicine, The University of Texas Rio Grande Valley, McAllen, TX 78504, USA
| | | | - Umaralikhan
- PG and Research Department of Physics, Jamal Mohamed College (Autonomous), Affiliated to Bharathidasan University, Tiruchirappalli 620020, Tamil Nadu, India
| | - Rotimi Sadiku
- Institute of Nano Engineering Research (INER), Department of Chemical, Metallurgical & Materials Engineering (Polymer Divison), Tshwane University of Technology, Pretoria West Campus, Staatsarillerie Rd, Pretoria 1083, South Africa
| |
Collapse
|
13
|
Ramesh M. N and Fe doped NiO nanoparticles for enhanced photocatalytic degradation of azo dye methylene blue in the presence of visible light. SN APPLIED SCIENCES 2021. [DOI: 10.1007/s42452-021-04803-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
AbstractPure NiO, N-doped, Fe-doped, N and Fe codoped NiO NPs were fabricated via a precipitation process. The powder X-ray diffraction (XRD) revealed the face centered cubic phase of NiO products. The full width at half maximum (FWHM) of the XRD peak was steadily enlarged with the order of elements N, Fe, N/Fe doped to NiO, and shifted towards a greater angle due to decrease in grain size, as shown by XRD. The average crystallite size of NiO products was calculated, ranging from 6.67 to 3.76 nm, according to the Debye Scherrer formula. The scanning electron microscopy (SEM) demonstrated considerable morphological changes in the produced nanoparticles, including those directed to rock-like geometries (NiO and Fe/NiO nanoparticles) while gas covered-nanocrystals (N/NiO and N/Fe/NiO nanoparticles) were formed using precipitation method. The particle size range of 10–50 nm was estimated using the bar scale in transmission electron microscopy (TEM) pictures. The elemental composition of Ni, O, Fe and N atoms in the respected samples was analyzed by Energy Dispersive X-Ray Analysis (EDX). Photoluminescence (PL) showed band edge emission at 370 nm. The band edge-absorption peak, which is caused by electronic transitions between energy levels, is determined to be in the range 314–325 nm. A UV–Vis analysis found an energy gap amid 3.2 eV and 2.5 eV. The chemical condition of the Fe and N doped NiO composites were validated using XPS. Using visible photo application of undoped and doped NiO NPs, the degradation of an azo dye termed methylene blue was examined. It was N/Fe/NiO (79.8%), Fe/NiO (76%), N/NiO (73%), and NiO (62%) throughout the 6 h irradiation duration. Increased production of OH• radicals was detected in fluorescence tests using terephthalic acid (TA) for N/Fe/NiO NPs, indicating the higher photo-degradation described. Furthermore, the degradation trends of both undoped and doped NiO NPs closely matched the pseudo first order kinetics, according to the kinetic analysis. There was also a suggestion for a thorough MB breakdown mechanism.
Collapse
|
14
|
Taeño M, Maestre D, Ramírez-Castellanos J, Li S, Lee PS, Cremades A. Towards Control of the Size, Composition and Surface Area of NiO Nanostructures by Sn Doping. NANOMATERIALS (BASEL, SWITZERLAND) 2021; 11:444. [PMID: 33578664 PMCID: PMC7916375 DOI: 10.3390/nano11020444] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 02/05/2021] [Accepted: 02/07/2021] [Indexed: 11/17/2022]
Abstract
Achieving nanostructures with high surface area is one of the most challenging tasks as this metric usually plays a key role in technological applications, such as energy storage, gas sensing or photocatalysis, fields in which NiO is gaining increasing attention recently. Furthermore, the advent of modern NiO-based devices can take advantage of a deeper knowledge of the doping process in NiO, and the fabrication of p-n heterojunctions. By controlling experimental conditions such as dopant concentration, reaction time, temperature or pH, NiO morphology and doping mechanisms can be modulated. In this work, undoped and Sn doped nanoparticles and NiO/SnO2 nanostructures with high surface areas were obtained as a result of Sn incorporation. We demonstrate that Sn incorporation leads to the formation of nanosticks morphology, not previously observed for undoped NiO, promoting p-n heterostructures. Consequently, a surface area value around 340 m2/g was obtained for NiO nanoparticles with 4.7 at.% of Sn, which is nearly nine times higher than that of undoped NiO. The presence of Sn with different oxidation states and variable Ni3+/Ni2+ ratio as a function of the Sn content were also verified by XPS, suggesting a combination of two charge compensation mechanisms (electronic and ionic) for the substitution of Ni2+ by Sn4+. These results make Sn doped NiO nanostructures a potential candidate for a high number of technological applications, in which implementations can be achieved in the form of NiO-SnO2 p-n heterostructures.
Collapse
Affiliation(s)
- María Taeño
- Departamento de Física de Materiales, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid, Spain; (D.M.); (A.C.)
| | - David Maestre
- Departamento de Física de Materiales, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid, Spain; (D.M.); (A.C.)
| | - Julio Ramírez-Castellanos
- Departamento de Química Inorgánica, Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040 Madrid, Spain;
| | - Shaohui Li
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore; (S.L.); (P.S.L.)
| | - Pooi See Lee
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore; (S.L.); (P.S.L.)
| | - Ana Cremades
- Departamento de Física de Materiales, Facultad de Ciencias Físicas, Universidad Complutense de Madrid, 28040 Madrid, Spain; (D.M.); (A.C.)
| |
Collapse
|
15
|
Santos R, Martins TA, Silva GN, Conceição MVS, Nogueira IC, Longo E, Botelho G. Ag 3PO 4/NiO Composites with Enhanced Photocatalytic Activity under Visible Light. ACS OMEGA 2020; 5:21651-21661. [PMID: 32905253 PMCID: PMC7469368 DOI: 10.1021/acsomega.0c02456] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2020] [Accepted: 07/31/2020] [Indexed: 05/05/2023]
Abstract
Black NiO powders were prepared by a hydrothermal method. Moreover, the visible light-driven Ag3PO4/NiO photocatalyst composites were successfully synthesized by in situ precipitation method. These samples were structurally characterized by X-ray diffraction and Rietveld refinement. The strong interaction between the phases and the defects in the samples was affected by the formation of the composites, as identified by Fourier transform infrared spectroscopy and Raman spectroscopy. UV-vis diffuse reflectance spectroscopy exhibited enhanced light absorption for all Ag3PO4/NiO composites, suggesting the effective interaction between the phases. Moreover, field-emission scanning electron microscopy images revealed the presence of NiO microflowers composed of nanoflakes in contact with Ag3PO4 microparticles. The composite with 5% NiO presented enhanced photocatalytic efficiency in comparison with pure Ag3PO4, degrading 96% of rhodamine B (RhB) dye in just 15 min under visible light; however, the recycling experiments confirmed that the composite with 75% NiO showed superior stability. The recombination of the electron-hole pairs was considered for the measurement of the photoluminescence of the samples. These measurements were performed to evaluate the possible causes for the difference in the photocatalytic responses of the composites. From these experimental results, possible photocatalytic mechanisms for RhB degradation over Ag3PO4/NiO composites under visible-light irradiation were proposed.
Collapse
Affiliation(s)
- Ricardo
K. Santos
- Department
of Environmental Chemistry, Federal University
of Tocantins, Gurupi, Tocantins 77402-970, Brazil
| | - Tiago A. Martins
- CDMF-UFSCar, Federal University of São Carlos, São Carlos, São
Paulo 13565-905, Brazil
| | - Gabriela N. Silva
- Department
of Environmental Chemistry, Federal University
of Tocantins, Gurupi, Tocantins 77402-970, Brazil
| | - Marcus V. S. Conceição
- Department
of Environmental Chemistry, Federal University
of Tocantins, Gurupi, Tocantins 77402-970, Brazil
| | - Içamira C. Nogueira
- Department
of Physics, Federal University of Amazonas, Manaus, Amazonas 69077-000, Brazil
| | - Elson Longo
- CDMF-UFSCar, Federal University of São Carlos, São Carlos, São
Paulo 13565-905, Brazil
| | - Gleice Botelho
- Department
of Environmental Chemistry, Federal University
of Tocantins, Gurupi, Tocantins 77402-970, Brazil
| |
Collapse
|
16
|
Hwang JD, Hwang YT. Enhancing ultraviolet-to-visible rejection ratio by inserting an intrinsic NiO layer in p-NiO/n-Si heterojunction photodiodes. NANOTECHNOLOGY 2020; 31:345205. [PMID: 32403098 DOI: 10.1088/1361-6528/ab92ca] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Conventionally, p-NiO/n-Si (p-n) heterojunction photodiodes (HPDs) exhibit a larger visible response than the ultraviolet response due to the thick Si substrate; hence, it is used as a broadband photodetector with a poor ultraviolet (UV)-to-visible rejection ratio. Herein, an intrinsic NiO (i-NiO) layer is inserted between the p-NiO and the n-Si substrate to fabricate p-NiO/i-NiO/n-Si (p-i-n) HPDs, significantly suppressing leakage current and visible response. Compared with the conventional p-n HPDs, the insertion of the i-NiO layer significantly reduces leakage current by approximately 241 times and enhances the rectification ratio from 13.8 to 3228 for the p-n and p-i-n HPDs. The insertion of an i-NiO layer not only increases the UV-response but also suppresses the visible response. These issues enhance the UV-to-visible rejection ratio from 72.2 in p-n HPDs to 915.3 in p-i-n HPDs. The p-NiO reveals a poorer crystalline structure than the i-NiO film because the Ag dopants accumulate at the grain boundary and inhibit crystalline growth. The Ag diffusion in the Si substrate causes defect states within the Si bandgap, whereas it is retarded by the i-NiO layer in the p-i-n HPDs. The poor crystallinity in the p-NiO and defect states within the Si bandgap contributes to a high leakage current and visible response in p-n HPDs. The p-i-n HPDs demonstrate a higher UV-response due to absorption by the i-NiO layer. Because visible light cannot be absorbed by the i-NiO layer, visible response is suppressed in p-i-n HPDs.
Collapse
Affiliation(s)
- J D Hwang
- Department of Electrophysics, National Chiayi University, No. 300 Syuefu Rd., Chiayi City 60004, Taiwan
| | | |
Collapse
|
17
|
Panigrahi UK, Sathe V, Babu PD, Mitra A, Mallick P. Effect of Mg doping on the improvement of photoluminescence and magnetic properties of NiO nanoparticles. NANO EXPRESS 2020. [DOI: 10.1088/2632-959x/aba285] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
|
18
|
Gandhi AC, Li TY, Kumar BV, Reddy PM, Peng JC, Wu CM, Wu SY. Room Temperature Magnetic Memory Effect in Cluster-Glassy Fe-doped NiO Nanoparticles. NANOMATERIALS 2020; 10:nano10071318. [PMID: 32635511 PMCID: PMC7407623 DOI: 10.3390/nano10071318] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Revised: 07/02/2020] [Accepted: 07/02/2020] [Indexed: 11/16/2022]
Abstract
The Fe-doped NiO nanoparticles that were synthesized using a co-precipitation method are characterized by enhanced room-temperature ferromagnetic property evident from magnetic measurements. Neutron powder diffraction experiments suggested an increment of the magnetic moment of 3d ions in the nanoparticles as a function of Fe-concentration. The temperature, time, and field-dependent magnetization measurements show that the effect of Fe-doping in NiO has enhanced the intraparticle interactions due to formed defect clusters. The intraparticle interactions are proposed to bring additional magnetic anisotropy energy barriers that affect the overall magnetic moment relaxation process and emerging as room temperature magnetic memory. The outcome of this study is attractive for the future development of the room temperature ferromagnetic oxide system to facilitate the integration of spintronic devices and understanding of their fundamental physics.
Collapse
Affiliation(s)
| | - Tai-Yue Li
- Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan; (A.C.G.); (T.-Y.L.)
| | - B. Vijaya Kumar
- Department of Chemistry, Nizam College, Osmania University, Hyderabad 500001, India;
| | - P. Muralidhar Reddy
- Department of Chemistry, University College of Science, Osmania University, Hyderabad 500007, Telangana, India;
| | - Jen-Chih Peng
- SIKA, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan; (J.-C.P.); (C.-M.W.)
| | - Chun-Ming Wu
- SIKA, National Synchrotron Radiation Research Center, Hsinchu 30076, Taiwan; (J.-C.P.); (C.-M.W.)
| | - Sheng Yun Wu
- Department of Physics, National Dong Hwa University, Hualien 97401, Taiwan; (A.C.G.); (T.-Y.L.)
- Correspondence: ; Tel.: +886-3-890-3717
| |
Collapse
|
19
|
Optical and Electrochemical Applications of Li-Doped NiO Nanostructures Synthesized via Facile Microwave Technique. MATERIALS 2020; 13:ma13132961. [PMID: 32630747 PMCID: PMC7372403 DOI: 10.3390/ma13132961] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2020] [Revised: 03/23/2020] [Accepted: 04/03/2020] [Indexed: 11/17/2022]
Abstract
Nanostructured NiO and Li-ion doped NiO have been synthesized via a facile microwave technique and simulated using the first principle method. The effects of microwaves on the morphology of the nanostructures have been studied by Field Emission Spectroscopy. X-ray diffraction studies confirm the nanosize of the particles and favoured orientations along the (111), (200) and (220) planes revealing the cubic structure. The optical band gap decreases from 3.3 eV (pure NiO) to 3.17 eV (NiO doped with 1% Li). Further, computational simulations have been performed to understand the optical behaviour of the synthesized nanoparticles. The optical properties of the doped materials exhibit violet, blue and green emissions, as evaluated using photoluminescence (PL) spectroscopy. In the presence of Li-ions, NiO nanoparticles exhibit enhanced electrical capacities and better cyclability. Cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) results show that with 1% Li as dopant, there is a marked improvement in the reversibility and the conductance value of NiO. The results are encouraging as the synthesized nanoparticles stand a better chance of being used as an active material for electrochromic, electro-optic and supercapacitor applications.
Collapse
|
20
|
Gandhi AC, Cheng CL, Wu SY. Structural and Enhanced Optical Properties of Stabilized γ‒Bi 2O 3 Nanoparticles: Effect of Oxygen Ion Vacancies. NANOMATERIALS 2020; 10:nano10061023. [PMID: 32471076 PMCID: PMC7352962 DOI: 10.3390/nano10061023] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/08/2020] [Revised: 05/20/2020] [Accepted: 05/22/2020] [Indexed: 01/04/2023]
Abstract
We report the synthesis of room temperature (RT) stabilized γ–Bi2O3 nanoparticles (NPs) at the expense of metallic Bi NPs through annealing in an ambient atmosphere. RT stability of the metastable γ–Bi2O3 NPs is confirmed using synchrotron radiation powder X-ray diffraction and Raman spectroscopy. γ–Bi2O3 NPs exhibited a strong red-band emission peaking at ~701 nm, covering 81% integrated intensity of photoluminescence spectra. Our findings suggest that the RT stabilization and enhanced red-band emission of γ‒Bi2O3 is mediated by excess oxygen ion vacancies generated at the octahedral O(2) sites during the annealing process.
Collapse
|
21
|
Metal organic framework–derived core-shell CuO@NiO nanosphares as hole transport material in perovskite solar cell. J Solid State Electrochem 2020. [DOI: 10.1007/s10008-020-04643-w] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
|
22
|
Contribution of enhanced ionization to the optoelectronic properties of p-type NiO films deposited by high power impulse magnetron sputtering. Ann Ital Chir 2019. [DOI: 10.1016/j.jeurceramsoc.2019.08.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
|
23
|
Rajivgandhi G, Maruthupandy M, Quero F, Li WJ. Graphene/nickel oxide nanocomposites against isolated ESBL producing bacteria and A549 cancer cells. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2019; 102:829-843. [PMID: 31147055 DOI: 10.1016/j.msec.2019.05.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2018] [Revised: 04/21/2019] [Accepted: 05/06/2019] [Indexed: 02/06/2023]
Abstract
The synthesis of nickel oxide nanoparticles (NiO NPs) and graphene/nickel oxide nanocomposites (Gr/NiO NCs) was performed using a simple chemical reduction method. Powder X-ray diffraction (XRD) and thermogravimetric analysis (TGA) were used to examine the crystalline nature and thermal stability of the synthesized NiO NPs and Gr/NiO NCs, respectively. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were utilized to observe the morphology of NiO NPs and Gr/NiO NCs and estimate their size range. TEM suggested that the NiO NPs were speared onto the surface of Gr nanosheet. The efficiency of NiO NPs and Gr/NiO NCs against extended spectrum β-lacamase (ESBL) producing bacteria, which was confirmed by specific HEXA disc Hexa G-minus 24 (HX-096) and MIC strip methods (CLSI); namely Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) was investigated using the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) methods. MIC results suggested that the NiO NPs and Gr/NiO NCs possess maximum growth inhibition of 86%, 82% and 94%, 92% at 50 and 30 μg/mL concentrations, respectively. Similarly, both nanomaterials were found to inhibit the β-lacamase enzyme at concentrations of 60 μg/mL and 40 μg/mL, respectively. The cytotoxicity of NiO NPs and Gr/NiO NCs was quantified against A549 human lung cancer cells. Cell death percentage values of 52% at 50 μg/mL against NiO NPs and 54% at 20 μg/mL against Gr/NiO NCs were obtained, respectively. The NCs were found to reduce cell viability, increase the level of reactive oxygen species (ROS) and modify both the mitochondrial membrane permeability and cell cycle arrest.
Collapse
Affiliation(s)
- Govindan Rajivgandhi
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China
| | - Muthuchamy Maruthupandy
- Laboratorio de Nanocelulosa y Biomateriales, Departamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Avenida Beauchef 851, Santiago, Chile.
| | - Franck Quero
- Laboratorio de Nanocelulosa y Biomateriales, Departamento de Ingeniería Química, Biotecnología y Materiales, Facultad de Ciencias Físicas y Matemáticas, Universidad de Chile, Avenida Beauchef 851, Santiago, Chile.
| | - Wen-Jun Li
- State Key Laboratory of Biocontrol and Guangdong Provincial Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, PR China
| |
Collapse
|
24
|
Beheshti A, Hashemi F, Abrahams CT. A new magnetic hybrid based on a unique sulfur rich cadmium coordination polymer used for high selective photocatalytic degradation of cationic dyes. J Taiwan Inst Chem Eng 2019. [DOI: 10.1016/j.jtice.2018.08.039] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
25
|
Wahyuono RA, Dellith A, Schmidt C, Dellith J, Ignaszak A, Seyring M, Rettenmayr M, Fize J, Artero V, Chavarot-Kerlidou M, Dietzek B. Structure of Ni(OH) 2 intermediates determines the efficiency of NiO-based photocathodes – a case study using novel mesoporous NiO nanostars. RSC Adv 2019; 9:39422-39433. [PMID: 35540634 PMCID: PMC9076120 DOI: 10.1039/c9ra08785k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2019] [Accepted: 11/22/2019] [Indexed: 12/29/2022] Open
Abstract
NiO nanostructures prepared from β-Ni(OH)2 intermediates exhibit favorable electronic properties for functional photocathodes for solar energy conversion devices.
Collapse
Affiliation(s)
- Ruri Agung Wahyuono
- Leibniz Institute of Photonic Technology (IPHT)
- Department Functional Interfaces
- 07745 Jena
- Germany
- Institute for Physical Chemistry and Abbe Center of Photonics
| | - Andrea Dellith
- Leibniz Institute of Photonic Technology (IPHT)
- Department Functional Interfaces
- 07745 Jena
- Germany
| | - Christa Schmidt
- Leibniz Institute of Photonic Technology (IPHT)
- Department Functional Interfaces
- 07745 Jena
- Germany
| | - Jan Dellith
- Leibniz Institute of Photonic Technology (IPHT)
- Department Functional Interfaces
- 07745 Jena
- Germany
| | - Anna Ignaszak
- Department of Chemistry
- University of New Brunswick
- Fredericton
- E3B 5A3 Canada
| | - Martin Seyring
- Otto Schott Institute of Materials Research (OSIM)
- Friedrich Schiller University Jena
- 07743 Jena
- Germany
| | - Markus Rettenmayr
- Otto Schott Institute of Materials Research (OSIM)
- Friedrich Schiller University Jena
- 07743 Jena
- Germany
| | - Jennifer Fize
- Univ. Grenoble Alpes
- CNRS
- CEA
- IRIG
- Laboratoire de Chimie et Biologie des Métaux
| | - Vincent Artero
- Univ. Grenoble Alpes
- CNRS
- CEA
- IRIG
- Laboratoire de Chimie et Biologie des Métaux
| | | | - Benjamin Dietzek
- Leibniz Institute of Photonic Technology (IPHT)
- Department Functional Interfaces
- 07745 Jena
- Germany
- Institute for Physical Chemistry and Abbe Center of Photonics
| |
Collapse
|
26
|
Kim HM, Kim J, Jang J. Quantum-dot light-emitting diodes with a perfluorinated ionomer-doped copper-nickel oxide hole transporting layer. NANOSCALE 2018; 10:7281-7290. [PMID: 29632918 DOI: 10.1039/c7nr09671b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Herein, we report all solution-processed green quantum-dot light-emitting diodes (G-QLEDs) by introducing a perfluorinated ionomer (PFI, Nafion 117) into quantum dots (QDs) to improve hole injection. To reduce the energy level mismatch between the hole transporting layer (HTL) and QDs and exciton quenching on the metal-oxide surface, a PFI-mixed copper-doped nickel oxide (Cu-NiO) HTL was introduced for G-QLEDs. Mixing Cu-NiO with a PFI increases the work function and induces phase separation between Cu-NiO and PFI; thus, energy band bending occurs on the surface such that effective hole injection can be possible. The phase-separated PFI molecules on HTL affect the thickness and compactness of G-QDs and make a smooth interface between G-QDs and HTL. The G-QLED with a PFI and Cu-NiO mixture HTL exhibits the maximum current efficiency (CEmax), power efficiency (PEmax), and external quantum efficiency (EQEmax) of 7.3 cd A-1, 2.1 lm W-1, and 2.14%, respectively, which are about 4 times those of the QLED with a Cu-NiO HTL.
Collapse
Affiliation(s)
- Hyo-Min Kim
- Department of Information Display and Advanced Display Research Center, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Korea.
| | | | | |
Collapse
|