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Wang P, Song C, Wang X, Chen H, Qian Y, Rao L, Zhou G, Nötzel R. Anisotropic Piezoelectric Response from InGaN Nanowires with Spatially Modulated Composition and Topography over a Textured Si(100) Substrate. ACS APPLIED MATERIALS & INTERFACES 2021; 13:7517-7528. [PMID: 33538580 DOI: 10.1021/acsami.0c17835] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
An anisotropic piezoelectric response is demonstrated from InGaN nanowires (NWs) over a pyramid-textured Si(100) substrate with an interfacet composition and topography modulation induced by stationary molecular beam epitaxy growth conditions, taking advantage of the unidirectional source beam flux. The variations of InGaN NWs between the pyramid facets are verified in terms of morphology, element distribution, and crystalline properties. The piezoelectric response is investigated by electrical atomic force microscopy (AFM) with a statistic analyzing method. Representative pyramids from the ensemble, on top of which InGaN NWs grown with a substrate held at an oblique angle, were characterized for understanding and confirming the degree of anisotropy. The positive deviated oscillation of the peak force error is identified as a measure of the effective AFM tip/NW interaction with respect to the electrical contact and mechanical deformation. The Schottky contact between the metal-coated AFM tip and the NWs on the different facets reveals distinctions consistent with the interfacet composition variation. The interfacet variation of the piezoelectric response of the InGaN NWs is first evaluated by electrical AFM under zero bias. The average current monotonically depends on the scan frequency, which determines the average peak force error, that is, mechanical deformation, with a facet characteristic slope. A piezoelectric nanogenerator device is fabricated out of a sample with an ensemble of pyramids, which exhibits anisotropic output under periodic directional pressing. This work provides a universal strategy for the synthesis of composite semiconductor materials with an anisotropic piezoelectric response.
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Affiliation(s)
- Peng Wang
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
| | - Changkun Song
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
| | - Xingfu Wang
- Institute of Semiconductor Science and Technology, South China Normal University, Guangzhou 510631, China
| | - Hedong Chen
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
| | - Yinping Qian
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
| | - Lujia Rao
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
| | - Guofu Zhou
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
- Academy of Shenzhen Guohua Optoelectronics, Shenzhen 518110, People's Republic of China
| | - Richard Nötzel
- Guangdong Provincial Key Laboratory of Optical Information Materials and Technology, South China Academy of Advanced Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
- National Center for International Research on Green Optoelectronics, South China Normal University, Guangzhou 510006, People's Republic of China
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Sun Q, Pan D, Li M, Zhao J, Chen P, Lu W, Zou J. In situ TEM observation of the vapor-solid-solid growth of <001[combining macron]> InAs nanowires. NANOSCALE 2020; 12:11711-11717. [PMID: 32452500 DOI: 10.1039/d0nr02892d] [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
In situ transmission electron microscopy characterization is a powerful method in investigating the growth mechanism of catalyst-induced semiconductor nanowires. By providing direct evidence on the crystal growth at the atomic level, a real-time in situ heating investigation was carried out on Au-catalyzed <001[combining macron]> InAs nanowires. It was found that the Au catalyst maintained itself in the solid form during the nanowire growth, and maintained a fixed epitaxial relationship with its underlying InAs nanowire, indicating the vapor-solid-solid mechanism. Importantly, the growth of <001[combining macron]> InAs nanowires through a layer-by-layer manner at the catalyst/nanowire interface is evident. This study provides direct insights into the vapor-solid-solid growth and clarified the growth mechanism of <001[combining macron]> III-V nanowires, which provides pathways in controlling the growth of <001[combining macron]> semiconductor nanowires.
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Affiliation(s)
- Qiang Sun
- Materials Engineering, The University of Queensland, St. Lucia, Queensland 4072, Australia.
| | - Dong Pan
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Meng Li
- Materials Engineering, The University of Queensland, St. Lucia, Queensland 4072, Australia.
| | - Jianhua Zhao
- State Key Laboratory of Superlattices and Microstructures, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China
| | - Pingping Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
| | - Wei Lu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083, China
| | - Jin Zou
- Materials Engineering, The University of Queensland, St. Lucia, Queensland 4072, Australia. and Centre for Microscopy and Microanalysis, The University of Queensland, St. Lucia, Queensland 4072, Australia
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Shen J, Yu Y, Wang J, Zheng Y, Gan Y, Li G. Insight into the Ga/In flux ratio and crystallographic plane dependence of MBE self-assembled growth of InGaN nanorods on patterned sapphire substrates. NANOSCALE 2020; 12:4018-4029. [PMID: 32016230 DOI: 10.1039/c9nr09767h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A controllable self-assembled growth using molecular beam epitaxy (MBE) of dense, uniform, and high-aspect-ratio InGaN nanorods (NRs) is achieved through regulating the Ga/In flux ratio and employing high Miller index planes of patterned sapphire substrates (PSSs). It is clearly demonstrated that both the low Ga/In flux ratio and high Miller index plane of PSS patterns facilitate the three-dimensional growth mode for InGaN NRs and simultaneously suppress NR coalescence. A lower Ga/In flux ratio favors a higher density, a larger aspect ratio, and a smaller coalescence degree of InGaN NRs through enhancing axial growth and inversely suppressing radial growth. The specific surface structures of high Miller index planes, e.g., the well-organized step-terrace and irregular bulge structures, critically affect the morphology, dimensions, density, and crystallographic orientation of MBE self-assembled NRs. In particular, the narrow and ordered step-terrace structure in the C3-plane-(4 5[combining macron] 1 38) plane-on a hexagonal pyramid favors the highest density, largest aspect ratio, and best uniformity of semipolar InGaN NRs, thus contributing to optimal photoluminescence performance. A thorough understanding of the mechanism of the effect of the Ga/In flux ratio and crystallographic plane on the MBE self-assembled growth behaviour of InGaN NRs was gained through experimental and theoretical exploration. This work contributes towards a deep understanding of the MBE self-assembled growth mechanism and controllable fabrication of dense, well-separated, and uniform InGaN NRs, thus contributing to the enhanced performance of NR-based optoelectronic devices.
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Affiliation(s)
- Jian Shen
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China. and School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China. and Center for Integrated Research of Future Electronics, and Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya 464-8601, Japan
| | - Yuefeng Yu
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China. and Engineering Research Center on Solid-State Lighting and its Informationisation of Guangdong Province, South China University of Technology, Guangzhou 510640, China
| | - Jia Wang
- Center for Integrated Research of Future Electronics, and Institute of Materials and Systems for Sustainability, Nagoya University, Nagoya 464-8601, Japan
| | - Yulin Zheng
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China. and Engineering Research Center on Solid-State Lighting and its Informationisation of Guangdong Province, South China University of Technology, Guangzhou 510640, China
| | - Yang Gan
- School of Chemistry and Chemical Engineering, Harbin Institute of Technology, Harbin 150001, China.
| | - Guoqiang Li
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China. and Engineering Research Center on Solid-State Lighting and its Informationisation of Guangdong Province, South China University of Technology, Guangzhou 510640, China
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Sun Q, Gao H, Zhang X, Yao X, Xu S, Zheng K, Chen P, Lu W, Zou J. High-quality epitaxial wurtzite structured InAs nanosheets grown in MBE. NANOSCALE 2020; 12:271-276. [PMID: 31819937 DOI: 10.1039/c9nr08429k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
In this study, we have grown epitaxial wurtzite structured InAs nanosheets using Au catalysts on a GaAs{111}B substrate by molecular beam epitaxy. Through detailed electron microscopy characterization studies on grown nanosheets, it was found that these wurtzite structured InAs nanosheets grew epitaxially on the GaAs{111}B substrate, with {0001[combining macron]} catalyst/nanosheet interfaces and extensive {112[combining macron]0} surfaces. It was anticipated that the epitaxially grown InAs nanosheet can be triggered by a high supersaturation in catalysts, leading to an inclined growth leaving the substrate surface, and driven by the small lattice mismatch between the nanosheets and the substrate, with the orientation relationship of (0001[combining macron])InAs//(112[combining macron])GaAs. This study provides insights into achieving epitaxial free-standing III-V nanosheet growth.
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Affiliation(s)
- Qiang Sun
- Materials Engineering, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Han Gao
- Materials Engineering, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Xutao Zhang
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yutian Road, Shanghai 200083, China and University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
| | - Xiaomei Yao
- Materials Engineering, The University of Queensland, St Lucia, Queensland 4072, Australia and State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yutian Road, Shanghai 200083, China and University of Chinese Academy of Sciences, No.19A Yuquan Road, Beijing 100049, China
| | - Shengduo Xu
- Materials Engineering, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Kun Zheng
- Institute of Microstructure and Properties of Advanced Materials, Beijing University of Technology, Beijing 100124, China
| | - Pingping Chen
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yutian Road, Shanghai 200083, China
| | - Wei Lu
- State Key Laboratory for Infrared Physics, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, 500 Yutian Road, Shanghai 200083, China and School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, China
| | - Jin Zou
- Materials Engineering, The University of Queensland, St Lucia, Queensland 4072, Australia and Centre for Microscopy and Microanalysis, The University of Queensland, St Lucia, Queensland 4072, Australia.
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Blumberg C, Liborius L, Ackermann J, Tegude FJ, Poloczek A, Prost W, Weimann N. Spatially controlled VLS epitaxy of gallium arsenide nanowires on gallium nitride layers. CrystEngComm 2020. [DOI: 10.1039/c9ce01926j] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
MOVPE of Au catalyzed p-GaAs nanowires on n-GaN layers. Left: VLS growth optimization (density and morphology). Middle and right: site-controlled pn-junctions by lateral and vertical anisotropic NWs in structured SiOx openings (scalebar 1 μm).
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Affiliation(s)
- C. Blumberg
- University of Duisburg-Essen
- Dept. Components for High Frequency Electronics
- Faculty of Engineering, and CENIDE
- Duisburg
- Germany
| | - L. Liborius
- University of Duisburg-Essen
- Dept. Components for High Frequency Electronics
- Faculty of Engineering, and CENIDE
- Duisburg
- Germany
| | - J. Ackermann
- University of Duisburg-Essen
- Dept. Components for High Frequency Electronics
- Faculty of Engineering, and CENIDE
- Duisburg
- Germany
| | - F.-J. Tegude
- University of Duisburg-Essen
- Dept. Components for High Frequency Electronics
- Faculty of Engineering, and CENIDE
- Duisburg
- Germany
| | - A. Poloczek
- University of Duisburg-Essen
- Dept. Components for High Frequency Electronics
- Faculty of Engineering, and CENIDE
- Duisburg
- Germany
| | - W. Prost
- University of Duisburg-Essen
- Dept. Components for High Frequency Electronics
- Faculty of Engineering, and CENIDE
- Duisburg
- Germany
| | - N. Weimann
- University of Duisburg-Essen
- Dept. Components for High Frequency Electronics
- Faculty of Engineering, and CENIDE
- Duisburg
- Germany
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Zheng Y, Wang W, Li Y, Lan J, Xia Y, Yang Z, He X, Li G. Self-Integrated Hybrid Ultraviolet Photodetectors Based on the Vertically Aligned InGaN Nanorod Array Assembly on Graphene. ACS APPLIED MATERIALS & INTERFACES 2019; 11:13589-13597. [PMID: 30892870 DOI: 10.1021/acsami.9b00940] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Integration of one-dimensional (1D) semiconductors with two-dimensional (2D) materials into hybrid systems is identified as promising applications for new optoelectronic and photodetection devices. Herein, a self-integrated hybrid ultraviolet (UV) photodetector based on InGaN nanorod arrays (NRAs) sandwiched between transparent top and back graphene contacts forming a Schottky junction has been demonstrated for the first time. The controlled van der Waals epitaxy of the vertically aligned InGaN NRA assembly on graphene-on-Si substrates is achieved by plasma-assisted molecular beam epitaxy. Moreover, the self-assembly formation mechanisms of InGaN NRAs on graphene are clarified by theoretical calculations with first-principles calculations based on density functional theory. The peculiar 1D/2D heterostructure hybrid system-based integrated UV photodetector simultaneously exhibits ultrafast response time (∼50 μs) and superhigh photosensitivity (∼105 A/W). It is highly believed that the concept proposed in this work has a great potential and can be widely applied for the next-generation integrated 1D/2D nano-based optoelectronic and photodetection devices.
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Affiliation(s)
- Yulin Zheng
- State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China
| | - Wenliang Wang
- State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China
- Guangdong Choicore Optoelectronics Co. Ltd. , Heyuan 517003 , China
| | - Yuan Li
- State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China
| | - Jianyu Lan
- State Key Laboratory of Space Technology , Shanghai Institute of Space Power Sources , Shanghai 200245 , China
| | - Yu Xia
- State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China
| | - Zhichao Yang
- State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China
| | - Xiaobin He
- State Key Laboratory of Space Technology , Shanghai Institute of Space Power Sources , Shanghai 200245 , China
| | - Guoqiang Li
- State Key Laboratory of Luminescent Materials and Devices , South China University of Technology , Guangzhou 510640 , China
- Guangdong Choicore Optoelectronics Co. Ltd. , Heyuan 517003 , China
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Shen J, Zheng Y, Xu Z, Yu Y, Gao F, Zhang S, Gan Y, Li G. Crystallographic plane and topography-dependent growth of semipolar InGaN nanorods on patterned sapphire substrates by molecular beam epitaxy. NANOSCALE 2018; 10:21951-21959. [PMID: 30444225 DOI: 10.1039/c8nr07307d] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
A low-cost, high-efficiency, and catalyst-free method for fabricating well-aligned and uniform semipolar InGaN nanorods (NRs) by molecular beam epitaxy (MBE) is proposed using an optimized patterned sapphire substrate (PSS) with high Miller index crystallographic planes. The dense, obliquely aligned, and high-quality semipolar (11[combining macron]02) InGaN NRs are fabricated on hexagonal pyramid arrays of the PSS for the first time in this work. A unique semipolar (11[combining macron]02) and polar (0001) InGaN NR array composite structure is thus achieved on a hexagonal pyramid PSS. The connected, uniform, and obliquely aligned NRs are formed on the PSS with cylindrical arrays. The cylindrical and hexagonal pyramid arrays of PSSs are structured by the standard photolithography process and etching techniques. Both pattern topography and crystallographic plane of the PSS significantly affect the morphology, dimension, and crystallographic orientation of InGaN NRs. It is clearly demonstrated that the PSS with exposed high Miller index crystallographic planes, with well-organized step-terrace structures, facilitates the growth of ordered and dense semipolar InGaN NRs. This work contributes to the thorough understanding of the nucleation and growth mechanisms of InGaN NRs on a high Miller index plane of the PSS with different topographies, as well as of those of controllably fabricating dense and uniform semipolar NRs, thus facilitating the fabrication of NR-based optoelectronic devices with enhanced performance.
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Affiliation(s)
- Jian Shen
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, China.
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Xu Z, Zhang S, Gao F, Wen L, Yu Y, Li G. Correlations among morphology, composition, and photoelectrochemical water splitting properties of InGaN nanorods grown by molecular beam epitaxy. NANOTECHNOLOGY 2018; 29:475603. [PMID: 30207545 DOI: 10.1088/1361-6528/aae0d4] [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
The mechanism underlying the effect of growth condition on the morphology evolution of InGaN nanorods (NRs) has been systematically investigated. The increased Ga flux enhances both the axial and the radial growth at the growth stage. However, the changed Ga flux influences not only the growth but also the nucleation of InGaN NRs. At the nucleation stage, the increased Ga flux shortens the delay time for NR formation, and prolongs the growth stage for a fixed total growth time. Those two aspects result in the increase of NR diameter and height with the supplied Ga flux. In addition, the continuous nucleation is ended much earlier due to the accelerated saturation of substrate area with the increased Ga flux, resulting in a decreased final NR density. In addition to the morphology evolution with the Ga flux, the composition characteristic of InGaN NRs has been also studied. The In distribution of InGaN NRs depends critically on the NR diameter along the NR growth direction, and the NRs show a morphology-dependent In incorporation. Interestingly, the InGaN NRs discussed here show a radial Stark effect induced by the pinned Fermi level. The radial Stark effect shifts the absorption edge of the InGaN NRs toward longer wavelengths, makes the InGaN NRs attractive for photoelectrochemical water splitting applications. The photoelectrochemical measurements present a significant increase in the photocurrent with the increased total surface area of the InGaN NRs, which is due to the enhanced light absorption effects and the enlarged interfacial area of the semiconductor/electrolyte.
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Affiliation(s)
- Zhenzhu Xu
- State Key Laboratory of Luminescent Materials and Devices, South China University of Technology, Guangzhou 510640, People's Republic of China. Engineering Research Center on Solid-State Lighting and its Informationisation of Guangdong Province, South China University of Technology, Guangzhou 510640, People's Republic of China
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Dahiya AS, Boubenia S, Franzo G, Poulin-Vittrant G, Mirabella S, Alquier D. Photoluminescence Study of the Influence of Additive Ammonium Hydroxide in Hydrothermally Grown ZnO Nanowires. NANOSCALE RESEARCH LETTERS 2018; 13:249. [PMID: 30136036 PMCID: PMC6104415 DOI: 10.1186/s11671-018-2665-4] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2018] [Accepted: 08/09/2018] [Indexed: 05/27/2023]
Abstract
We report the influence of ammonium hydroxide (NH4OH), as growth additive, on zinc oxide nanomaterial through the optical response obtained by photoluminescence (PL). A low-temperature hydrothermal process is employed for the growth of ZnO nanowires (NWs) on seedless Au surface. A more than two order of magnitude change in ZnO NW density is demonstrated via careful addition of NH4OH in the growth solution. Further, we show by systematic experimental study and PL characterization data that the addition of NH4OH can degrade the optical response of ZnO NWs produced. The increase of growth solution basicity with the addition of NH4OH may slowly degrade the optical response of NWs by slowly etching its surfaces, increasing the point defects in ZnO NWs. The present study demonstrates the importance of growth nutrients to obtain quality controlled density tunable ZnO NWs on seedless conducting substrates.
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Affiliation(s)
- A. S. Dahiya
- GREMAN UMR 7347 Université de Tours, CNRS, INSA Centre Val de Loire, 16 rue Pierre et Marie Curie, 37071 Tours CEDEX2, France
| | - S. Boubenia
- GREMAN UMR 7347 Université de Tours, CNRS, INSA Centre Val de Loire, 16 rue Pierre et Marie Curie, 37071 Tours CEDEX2, France
| | - G. Franzo
- MATIS IMM-CNR and Dipartimento di Fisica e Astronomia, Universita’ di Catania, via S. Sofia 64, 95123 Catania, Italy
| | - G. Poulin-Vittrant
- GREMAN UMR 7347 CNRS, Université de Tours, INSA Centre Val de Loire, 3 rue de la Chocolaterie, CS 23410, 41034 Blois CEDEX, France
| | - S. Mirabella
- MATIS IMM-CNR and Dipartimento di Fisica e Astronomia, Universita’ di Catania, via S. Sofia 64, 95123 Catania, Italy
| | - D. Alquier
- GREMAN UMR 7347 Université de Tours, CNRS, INSA Centre Val de Loire, 16 rue Pierre et Marie Curie, 37071 Tours CEDEX2, France
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