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Sharu K, Chattopadhyay S, Prajapati KN, Mitra J. Leveraging plasmonic hot electrons to quench defect emission in metal-semiconductor nanostructured hybrids. J Chem Phys 2023; 159:244702. [PMID: 38146830 DOI: 10.1063/5.0171078] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2023] [Accepted: 12/04/2023] [Indexed: 12/27/2023] Open
Abstract
Modeling light-matter interactions in hybrid plasmonic materials is vital to their widening relevance from optoelectronics to photocatalysis. Here, we explore photoluminescence (PL) from ZnO nanorods (ZNRs) embedded with gold nanoparticles (Au NPs). A progressive increase in Au NP concentration introduces significant structural disorder and defects in ZNRs, which paradoxically quenches defect related visible PL while intensifying the near band edge (NBE) emission. Under UV excitation, the simulated semi-classical model realizes PL from ZnO with sub-bandgap defect states, eliciting visible emissions that are absorbed by Au NPs to generate a non-equilibrium hot carrier distribution. The photo-stimulated hot carriers, transferred to ZnO, substantially modify its steady-state luminescence, reducing NBE emission lifetime and altering the abundance of ionized defect states, finally reducing visible emission. The simulations show that the change in the interfacial band bending at the Au-ZnO interface under optical illumination facilitates charge transfer between the components. This work provides a general foundation to observe and model the hot carrier dynamics and strong light-matter interactions in hybrid plasmonic systems.
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Affiliation(s)
- Kritika Sharu
- School of Physics, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - Shashwata Chattopadhyay
- School of Physics, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - K N Prajapati
- School of Physics, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
| | - J Mitra
- School of Physics, Indian Institute of Science Education and Research Thiruvananthapuram, Thiruvananthapuram, Kerala 695551, India
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Chen Z, Liu W, Si X, Guo J, Huo J, Zhang Z, Cheng G, Du Z. In situ assembly of one-dimensional Pt@ZnO nanofibers driven by a ZIF-8 framework for achieving a high-performance acetone sensor. NANOSCALE 2023; 15:17206-17215. [PMID: 37855215 DOI: 10.1039/d3nr04040b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/20/2023]
Abstract
To obtain a high-performance gas sensor, it is essential to ingeniously design sensing materials containing the features of high catalytic performance, abundant oxygen vacancies, and splendid grain dispersibility through a simple method. Inspired by the fact that ZIF-8 contains semiconductor metal atoms, well-arranged ZnO nanoparticle (NP)-in situ assembled one-dimensional nanofibers (NFs) are obtained by one-step electrospinning. By incorporating Pt NPs into the cavity of ZIF-8 NPs, well-dispersed Pt@ZnO NPs driven by Pt@ZIF-8 composites are obtained after annealing. The well-arranged Pt@ZnO NP-assembled NFs not only exhibit abundant oxygen vacancies but also avoid the self-aggregation of ZnO and Pt NPs. Meanwhile, the small Pt NPs could improve the catalytic effect in return. Therefore, the gas sensor fabricated based on the above materials exhibits an acetone sensitivity of 6.1 at 370 °C, compared with pristine ZnO NFs (1.6, 5 ppm). Moreover, the well-arranged Pt@ZnO NP-assembled NFs show exceptional sensitivity to acetone with a 70.2 ppb-level detection limit in theory. The synergistic advantages of the designed sensing material open up new possibilities for non-invasive disease diagnosis.
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Affiliation(s)
- Zaiping Chen
- Key Lab for Special Functional Materials, Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China.
| | - Wei Liu
- Key Lab for Special Functional Materials, Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China.
| | - Xiaohui Si
- Key Lab for Special Functional Materials, Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China.
| | - Junmeng Guo
- Key Lab for Special Functional Materials, Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China.
| | - Jiahang Huo
- Key Lab for Special Functional Materials, Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China.
| | - Zhiheng Zhang
- Key Lab for Special Functional Materials, Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China.
| | - Gang Cheng
- Key Lab for Special Functional Materials, Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China.
| | - Zuliang Du
- Key Lab for Special Functional Materials, Ministry of Education, National & Local Joint Engineering Research Center for High-efficiency Display and Lighting Technology, School of Materials Science and Engineering, and Collaborative Innovation Center of Nano Functional Materials and Applications, Henan University, Kaifeng 475004, China.
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3
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Banerjee D, Banerjee P, Kar AK. Insights into the impact of photophysical processes and defect state evolution on the emission properties of surface-modified ZnO nanoplates for application in photocatalysis and hybrid LEDs. Phys Chem Chem Phys 2022; 24:2424-2440. [PMID: 35019914 DOI: 10.1039/d1cp05110e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The effects of surface modification on the defect state densities, optical properties, and photocatalytic and quantum efficiencies of zinc oxide (ZnO) nanoplates were studied in this work. The aim of this study is to identify the photophysical processes that dictate the quenching of emission from defect states upon surface modification and the role of different defects such as zinc interstitials (Zni) or oxygen vacancies (VO) beside the photophysical processes in determining the photocatalytic efficiency of plate-like ZnO nanostructures. For controlling the intrinsic defect state densities of ZnO nanoplates, which is difficult to achieve, their surface was modified using different polymers such as PMMA and PVA. X-ray photoelectron spectroscopy (XPS) and photoluminescence (PL) emission spectroscopy were employed to identify and quantify the defect states. The analysis of relative defect state densities of Zni or VO showed that Zni significantly impacts the photocatalytic activity (PCA) besides VO, but it has a lower influence than VO because of the difference in the accessibility and intrinsic nature of these two defects. Synchronous quenching of emission from different defect states with different formation energies and its correlation with the photocatalytic activity led us to conclude that photophysical processes such as concentration-dependent Förster resonance energy transfer (FRET), charge transfer (CT) and Zni defects play a significant role behind PCA, which has been previously reported to be influenced by VO only. FRET and CT also play a critical role behind emission quenching upon surface modification. Upon the surface modification of nanoplates, a drop in the quantum efficiency from 12.14% to 4.44% was observed with the fine-tuning of emission colour from bluish-white to blue. Besides the defect states, FRET and CT phenomena are dominant in reducing the quantum efficiency of hybrid light-emitting diodes (HyLEDs) and photocatalytic efficiency. Therefore, the work outlines the reason behind the suppression of luminescence and photocatalytic efficiency of ZnO nanoparticles after surface modification and how to optimise them for their applications as an emissive layer in HyLEDs and efficient photocatalysts.
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Affiliation(s)
- Dhritiman Banerjee
- Micro and Nano Science Laboratory, Department of Physics, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, 826004, India.
| | - Payal Banerjee
- Department of Chemistry, National Tsing Hua University, Hsinchu, 300044, Taiwan
| | - Asit Kumar Kar
- Micro and Nano Science Laboratory, Department of Physics, Indian Institute of Technology (Indian School of Mines), Dhanbad, Jharkhand, 826004, India.
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Localized Energy Band Bending in ZnO Nanorods Decorated with Au Nanoparticles. NANOMATERIALS 2021; 11:nano11102718. [PMID: 34685157 PMCID: PMC8539582 DOI: 10.3390/nano11102718] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/06/2021] [Revised: 10/05/2021] [Accepted: 10/12/2021] [Indexed: 11/25/2022]
Abstract
Surface decoration by means of metal nanostructures is an effective way to locally modify the electronic properties of materials. The decoration of ZnO nanorods by means of Au nanoparticles was experimentally investigated and modelled in terms of energy band bending. ZnO nanorods were synthesized by chemical bath deposition. Decoration with Au nanoparticles was achieved by immersion in a colloidal solution obtained through the modified Turkevich method. The surface of ZnO nanorods was quantitatively investigated by Scanning Electron Microscopy, Transmission Electron Microscopy and Rutherford Backscattering Spectrometry. The Photoluminescence and Cathodoluminescence of bare and decorated ZnO nanorods were investigated, as well as the band bending through Mott–Schottky electrochemical analyses. Decoration with Au nanoparticles induced a 10 times reduction in free electrons below the surface of ZnO, together with a decrease in UV luminescence and an increase in visible-UV intensity ratio. The effect of decoration was modelled with a nano-Schottky junction at ZnO surface below the Au nanoparticle with a Multiphysics approach. An extensive electric field with a specific halo effect formed beneath the metal–semiconductor interface. ZnO nanorod decoration with Au nanoparticles was shown to be a versatile method to tailor the electronic properties at the semiconductor surface.
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A Simple Ball Milling and Thermal Oxidation Method for Synthesis of ZnO Nanowires Decorated with Cubic ZnO 2 Nanoparticles. NANOMATERIALS 2021; 11:nano11020475. [PMID: 33668447 PMCID: PMC7918776 DOI: 10.3390/nano11020475] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 01/30/2021] [Accepted: 02/05/2021] [Indexed: 11/17/2022]
Abstract
In this work, we propose the synthesis of ZnO nanostructures through the thermal oxidation of ball-milled powders with the introduction of Mg and Sn doping species at the preliminary step of milling. We investigate the advantages and challenges of this two steps process for the production and fabrication of highly crystalline ZnO nanowires. This simple method allows us to fabricate ZnO nanowires with a higher quality core crystal at a much lower temperature and for a shorter processing time than the state-of-the-art, and decorated with by ZnO2 nanoparticles as determined via TEM analysis. The main findings will show that the crystalline core of the nanowires is of hexagonal ZnO while the nanoparticles on the surface are ZnO2 cubic type. Generally, the method proves to be suitable for applications that require a high surface-to-volume ratio, for example, catalysis phenomena, in which the presence of zinc oxides species can play an important role.
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Guo X, Li J, Arabi M, Wang X, Wang Y, Chen L. Molecular-Imprinting-Based Surface-Enhanced Raman Scattering Sensors. ACS Sens 2020; 5:601-619. [PMID: 32072805 DOI: 10.1021/acssensors.9b02039] [Citation(s) in RCA: 83] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Molecularly imprinted polymers (MIPs) receive extensive interest, owing to their structure predictability, recognition specificity, and application universality as well as robustness, simplicity, and inexpensiveness. Surface-enhanced Raman scattering (SERS) is regarded as an ideal optical detection candidate for its unique features of fingerprint recognition, nondestructive property, high sensitivity, and rapidity. Accordingly, MIP based SERS (MIP-SERS) sensors have attracted significant research interest for versatile applications especially in the field of chemo- and bioanalysis, showing excellent identification and detection performances. Herein, we comprehensively review the recent advances in MIP-SERS sensors construction and applications, including sensing principles and signal enhancement mechanisms, focusing on novel construction strategies and representative applications. First, the basic structure of the MIP-SERS sensors is briefly outlined. Second, novel imprinting strategies are highlighted, mainly including multifunctional monomer imprinting, dummy template imprinting, living/controlled radical polymerization, and stimuli-responsive imprinting. Third, typical application of MIP-SERS sensors in chemo/bioanalysis is summarized from both small and macromolecular aspects. Lastly, the challenges and perspectives of the MIP-SERS sensors are proposed, orienting sensitivity improvement and application expanding.
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Affiliation(s)
- Xiaotong Guo
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Research Center for Coastal Environmental Engineering and Technology, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jinhua Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Research Center for Coastal Environmental Engineering and Technology, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao 266071, China
| | - Maryam Arabi
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Research Center for Coastal Environmental Engineering and Technology, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
| | - Xiaoyan Wang
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Research Center for Coastal Environmental Engineering and Technology, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
| | - Yunqing Wang
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Research Center for Coastal Environmental Engineering and Technology, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
| | - Lingxin Chen
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Research Center for Coastal Environmental Engineering and Technology, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, China
- School of Pharmacy, Binzhou Medical University, Yantai 264003, China
- College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu 273165, China
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7
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Prajapati KN, Johns B, Bandopadhyay K, Silva SRP, Mitra J. Interaction of ZnO nanorods with plasmonic metal nanoparticles and semiconductor quantum dots. J Chem Phys 2020; 152:064704. [PMID: 32061232 DOI: 10.1063/1.5138944] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We model the enhancement of near band edge emission from ZnO nanorods using plasmonic metal nanoparticles and compare it with emission enhancement from ZnO with semiconducting quantum dots. Selected CdSe quantum dots with absorption energies close to those of Ag and Au nanoparticles are chosen to construct model systems with ZnO to comprehend the role of ZnO's intrinsic defects and plasmonic excitation in realizing the spectrally selective luminescence enhancement. Excitation wavelength dependent photoluminescence spectra along with theoretical models quantifying the related transitions and plasmonic absorption reveal that a complex mechanism of charge transfer between the ZnO nanorods and metal nanoparticles or quantum dots is essential along with an optimal energy band alignment for realizing emission enhancement. The theoretical model presented also provides a direct method of quantifying the relative transition rate constants associated with various electronic transitions in ZnO and their change upon the incorporation of plasmonic nanoparticles. The results indicate that, while the presence of deep level defect states may facilitate the essential charge transfer process between ZnO and the plasmonic nanoparticles, their presence alone does not guarantee UV emission enhancement and strong plasmonic coupling between the two systems. The results offer clues to designing novel multicomponent systems with coupled plasmonic and charge transfer effects for applications in charge localization, energy harvesting, and luminescence enhancement, especially in electrically triggered nanophotonic applications.
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Affiliation(s)
- K N Prajapati
- School of Physics, Indian Institute of Science Education and Research, Thiruvananthapuram 695551, India
| | - Ben Johns
- School of Physics, Indian Institute of Science Education and Research, Thiruvananthapuram 695551, India
| | - K Bandopadhyay
- Department of Functional Materials, Łukasiewicz Research Network-Institute of Electronic Materials Technology, Wolczynska 133, Warsaw, Poland
| | - S Ravi P Silva
- Advanced Technology Institute, University of Surrey, Guildford GU2 7XH, United Kingdom
| | - J Mitra
- School of Physics, Indian Institute of Science Education and Research, Thiruvananthapuram 695551, India
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8
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Synthesis of Au/SnO 2 nanostructures allowing process variable control. Sci Rep 2020; 10:346. [PMID: 31941987 PMCID: PMC6962171 DOI: 10.1038/s41598-019-57222-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2019] [Accepted: 12/23/2019] [Indexed: 11/08/2022] Open
Abstract
Theoretical advances in science are inherently time-consuming to realise in engineering, since their practical application is hindered by the inability to follow the theoretical essence. Herein, we propose a new method to freely control the time, cost, and process variables in the fabrication of a hybrid featuring Au nanoparticles on a pre-formed SnO2 nanostructure. The above advantages, which were divided into six categories, are proven to be superior to those achieved elsewhere, and the obtained results are found to be applicable to the synthesis and functionalisation of other nanostructures. Furthermore, the reduction of the time-gap between science and engineering is expected to promote the practical applications of numerous scientific theories.
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9
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Shahine I, Jradi S, Beydoun N, Gaumet J, Akil S. Plasmon‐Enhanced Photoluminescence and Photocatalysis Reactions in Metal‐Semiconductor Nanomaterials: UV‐Generated Hot Electron in Gold‐Zinc Oxide. CHEMPHOTOCHEM 2019. [DOI: 10.1002/cptc.201900252] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Issraa Shahine
- LCP−A2MC, Institut Jean BarriolUniversité de Lorraine 1 Boulevard Arago 57070 Metz France
| | - Safi Jradi
- L2n, Lumière, Nanomatériaux, Nanotechnologies ICD, CNRSUniversité de Technologie de Troyes 12 Rue Marie-Curie 10004 Troyes France
| | - Nour Beydoun
- L2n, Lumière, Nanomatériaux, Nanotechnologies ICD, CNRSUniversité de Technologie de Troyes 12 Rue Marie-Curie 10004 Troyes France
| | - Jean‐Jacques Gaumet
- LCP−A2MC, Institut Jean BarriolUniversité de Lorraine 1 Boulevard Arago 57070 Metz France
| | - Suzanna Akil
- LCP−A2MC, Institut Jean BarriolUniversité de Lorraine 1 Boulevard Arago 57070 Metz France
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10
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Abstract
The passivation effects of SF6 plasma on zinc oxide (ZnO) films prepared by magnetron sputtering were researched. After the SF6 plasma passivation of ZnO films, the grain size increases, there is low surface roughness, and a small amount of Zn-F bonds are formed, resulting in the narrowing of band gap. The photoluminescence (PL) intensity of SF6-passivated ZnO films has a 120% increase compared to the untreated samples, and the reduction in defects can increase the resistivity and stability of ZnO films. ZnO films are used in the preparation of ZnO/p-Si heterojunction diodes. The results of the measurement of current voltage (J–V) show that the reverse current is reduced after SF6 plasma passivation, indicating an improvement in the electrical properties of ZnO films.
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Alsultany FH, Majdi HS, Abd HR, Hassan Z, Ahmed NM. Catalytic Growth of 1D ZnO Nanoneedles on Glass Substrates Through Vapor Transport. JOURNAL OF ELECTRONIC MATERIALS 2019; 48:1660-1668. [DOI: 10.1007/s11664-018-06853-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Accepted: 12/04/2018] [Indexed: 09/02/2023]
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Garg V, Sengar BS, Awasthi V, Kumar A, Singh R, Kumar S, Mukherjee C, Atuchin VV, Mukherjee S. Investigation of Dual-Ion Beam Sputter-Instigated Plasmon Generation in TCOs: A Case Study of GZO. ACS APPLIED MATERIALS & INTERFACES 2018; 10:5464-5474. [PMID: 29356500 DOI: 10.1021/acsami.7b15103] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The use of the high free-electron concentration in heavily doped semiconductor enables the realization of plasmons. We report a novel approach to generate plasmons in Ga:ZnO (GZO) thin films in the wide spectral range of ∼1.87-10.04 eV. In the grown GZO thin films, dual-ion beam sputtering (DIBS) instigated plasmon is observed because of the formation of different metallic nanoclusters are reported. Moreover, formation of the nanoclusters and generation of plasmons are verified by field emission scanning electron microscope, electron energy loss spectra obtained by ultraviolet photoelectron spectroscopy, and spectroscopic ellipsometry analysis. Moreover, the calculation of valence bulk, valence surface, and particle plasmon resonance energies are performed, and indexing of each plasmon peaks with corresponding plasmon energy peak of the different nanoclusters is carried out. Further, the use of DIBS-instigated plasmon-enhanced GZO can be a novel mean to improve the performance of photovoltaic, photodetector, and sensing devices.
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Affiliation(s)
- Vivek Garg
- Hybrid Nanodevice Research Group (HNRG), Electrical Engineering, Indian Institute of Technology (IIT) Indore , Indore 453552, Madhya Pradesh, India
| | - Brajendra S Sengar
- Hybrid Nanodevice Research Group (HNRG), Electrical Engineering, Indian Institute of Technology (IIT) Indore , Indore 453552, Madhya Pradesh, India
| | - Vishnu Awasthi
- Hybrid Nanodevice Research Group (HNRG), Electrical Engineering, Indian Institute of Technology (IIT) Indore , Indore 453552, Madhya Pradesh, India
| | - Amitesh Kumar
- Hybrid Nanodevice Research Group (HNRG), Electrical Engineering, Indian Institute of Technology (IIT) Indore , Indore 453552, Madhya Pradesh, India
| | - Rohit Singh
- Hybrid Nanodevice Research Group (HNRG), Electrical Engineering, Indian Institute of Technology (IIT) Indore , Indore 453552, Madhya Pradesh, India
| | - Shailendra Kumar
- Raja Ramanna Center for Advanced Technology , Indore 452013, India
| | - C Mukherjee
- Advanced Laser and Optics Division, Raja Ramanna Center for Advanced Technology , Indore 452013, India
- Homi Bhabha National Institute , Training School Complex, Anushakti Nagar, Mumbai 400094, India
| | - V V Atuchin
- Laboratory of Optical Materials and Structures, Institute of Semiconductor Physics, SB RAS , Novosibirsk 630090, Russia
- Functional Electronics Laboratory, Tomsk State University , Tomsk 634050, Russia
- Laboratory of Single Crystal Growth, South Ural State University , Chelyabinsk 454080, Russia
| | - Shaibal Mukherjee
- Hybrid Nanodevice Research Group (HNRG), Electrical Engineering, Indian Institute of Technology (IIT) Indore , Indore 453552, Madhya Pradesh, India
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Neogi A, Gryczynski K, Llopis A, Lin J, Main K, Shimada R, Wang Z, Lee J, Salamo G, Krokhin A. Metallic Nanodroplet Induced Coulomb Catalysis for Off-Resonant Plasmonic Enhancement of Photoemission in Semiconductors. ACS OMEGA 2016; 1:19-28. [PMID: 31457115 PMCID: PMC6640769 DOI: 10.1021/acsomega.6b00009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Accepted: 06/14/2016] [Indexed: 06/09/2023]
Abstract
The enhancement of light from semiconductors due to surface plasmons coupled resonantly to its emission is limited because of dissipation in the metal and is also restricted by the dielectric characteristics and homogeneity of the metal-semiconductor interface. We report a new mechanism based on electrostatic interactions of carriers and their image charges in metals to generate more photons from optical sources at frequencies that are off-resonant to the localized plasmon frequency. Coulomb catalysis of carrier accumulation resulting from the inhomogeneity of metal nanodroplets on a semiconductor's surface can result in an enhancement of light that is nondissipative and does not require resonant coupling of plasmons to the emission wavelength. The enhancement occurs because of an increase in the ratio of radiative to nonradiative recombination in the vicinity of metal nanoparticles. It is equally effective with any type of metal and enhances radiation at any frequency, a property that is of principal importance for the realization of widely tunable semiconductor emitters. This fundamental mechanism provides a new perspective for improving the efficiency of light emitters and controlling carrier concentration on the nanoscale. The structural characteristics of the hybrid metal-semiconductor emitters are studied using electron microscopy and atomic force microscopy. We demonstrate the electrostatic mechanism by studying steady-state and transient photoluminescence from two-dimensional semiconductors, such as GaAs/AlGAs quantum wells, and bulk semiconductors, such as ZnO thin films, emitting in the near-IR and UV wavelength regimes, respectively.
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Affiliation(s)
- Arup Neogi
- Institute
of Fundamental and Frontier Sciences, University
of Electronic Science and Technology of China, Chengdu 610054, P.R. China
- Department
of Physics, University of North Texas, 211 Avenue A, Denton, Texas 76203, United States
- Advanced
Materials Manufacturing Process Institute, UNT Discovery Park, 3940 North Elm Street, #E132, Denton, Texas 76207-7102, United States
| | - Karol Gryczynski
- Department
of Physics, University of North Texas, 211 Avenue A, Denton, Texas 76203, United States
| | - Antonio Llopis
- Department
of Physics, University of North Texas, 211 Avenue A, Denton, Texas 76203, United States
| | - Jie Lin
- Department
of Physics, University of North Texas, 211 Avenue A, Denton, Texas 76203, United States
| | - Kyle Main
- Department
of Physics, University of North Texas, 211 Avenue A, Denton, Texas 76203, United States
| | - Ryoko Shimada
- Department
of Physics and Mathematical Sciences, Japan
Women University, 2-8-1
Mejirodai, Bunkyo-ku, Tokyo 112-8681, Japan
| | - Zhiming Wang
- Institute
of Fundamental and Frontier Sciences, University
of Electronic Science and Technology of China, Chengdu 610054, P.R. China
| | - Jihoon Lee
- College
of Electronics and Information, Kwangwoon
University, 447-1 Wolgye-dong, Nowon-gu, Seoul 139-701, South Korea
| | - Gregory Salamo
- Department
of Physics, University of Arkansas, Fayetteville, Arkansas 72701, United States
| | - Arkadii Krokhin
- Department
of Physics, University of North Texas, 211 Avenue A, Denton, Texas 76203, United States
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15
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Modepalli V, Jin MJ, Park J, Jo J, Kim JH, Baik JM, Seo C, Kim J, Yoo JW. Gate-Tunable Spin Exchange Interactions and Inversion of Magnetoresistance in Single Ferromagnetic ZnO Nanowires. ACS NANO 2016; 10:4618-4626. [PMID: 26964013 DOI: 10.1021/acsnano.6b00921] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Electrical control of ferromagnetism in semiconductor nanostructures offers the promise of nonvolatile functionality in future semiconductor spintronics. Here, we demonstrate a dramatic gate-induced change of ferromagnetism in ZnO nanowire (NW) field-effect transistors (FETs). Ferromagnetism in our ZnO NWs arose from oxygen vacancies, which constitute deep levels hosting unpaired electron spins. The magnetic transition temperature of the studied ZnO NWs was estimated to be well above room temperature. The in situ UV confocal photoluminescence (PL) study confirmed oxygen vacancy mediated ferromagnetism in the studied ZnO NW FET devices. Both the estimated carrier concentration and temperature-dependent conductivity reveal the studied ZnO NWs are at the crossover of the metal-insulator transition. In particular, gate-induced modulation of the carrier concentration in the ZnO NW FET significantly alters carrier-mediated exchange interactions, which causes even inversion of magnetoresistance (MR) from negative to positive values. Upon sweeping the gate bias from -40 to +50 V, the MRs estimated at 2 K and 2 T were changed from -11.3% to +4.1%. Detailed analysis on the gate-dependent MR behavior clearly showed enhanced spin splitting energy with increasing carrier concentration. Gate-voltage-dependent PL spectra of an individual NW device confirmed the localization of oxygen vacancy-induced spins, indicating that gate-tunable indirect exchange coupling between localized magnetic moments played an important role in the remarkable change of the MR.
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Affiliation(s)
- Vijayakumar Modepalli
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Mi-Jin Jin
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Jungmin Park
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Junhyeon Jo
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Ji-Hyun Kim
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Jeong Min Baik
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
| | - Changwon Seo
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University , Suwon 440-746, Republic of Korea
- Department of Energy Science, Sungkyunkwan University , Suwon 440-746, Republic of Korea
| | - Jeongyong Kim
- Center for Integrated Nanostructure Physics, Institute for Basic Science, Sungkyunkwan University , Suwon 440-746, Republic of Korea
- Department of Energy Science, Sungkyunkwan University , Suwon 440-746, Republic of Korea
| | - Jung-Woo Yoo
- School of Materials Science and Engineering-Low dimensional Carbon Materials Center, Ulsan National Institute of Science and Technology , Ulsan 689-798, Republic of Korea
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16
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Wang L, Wang X, Mao S, Wu H, Guo X, Ji Y, Han X. Strongly enhanced ultraviolet emission of an Au@SiO2/ZnO plasmonic hybrid nanostructure. NANOSCALE 2016; 8:4030-4036. [PMID: 26818908 DOI: 10.1039/c5nr06153a] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We present the surface plasmon polariton (SPP)-enhanced ultraviolet (UV) emission of an Au@SiO2/ZnO hybrid nanostructure. We achieved approximately 20- and 8-fold enhancements of the UV-emitting intensities from Au-SPP coupled nanometre- and micrometre-scaled ZnO wires through an optimized 5 nm-thick SiO2 spacer compared to that obtained from bare ZnO on a Si substrate without SPP coupling. Cathodoluminescence measurements and simulations demonstrated that the plasmonic hybrid nanostructure enables the strong localization of the SPP field, resulting in significantly enhanced UV emission. This plasmonic structure paves the way to nanoscale UV-optical lasers and sensors.
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Affiliation(s)
- Li Wang
- Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing, 100124, P.R. China. and Beijing Key Lab of Microstructure and Property of Advanced Material, Beijing University of Technology, Beijing, 100124, P.R. China
| | - Xiaodong Wang
- Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing, 100124, P.R. China. and Beijing Key Lab of Microstructure and Property of Advanced Material, Beijing University of Technology, Beijing, 100124, P.R. China
| | - Shengcheng Mao
- Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing, 100124, P.R. China. and Beijing Key Lab of Microstructure and Property of Advanced Material, Beijing University of Technology, Beijing, 100124, P.R. China
| | - Hua Wu
- College of Electronic Information & Control Engineering, Beijing University of Technology, Beijing, 100124, P.R. China
| | - Xia Guo
- College of Electronic Information & Control Engineering, Beijing University of Technology, Beijing, 100124, P.R. China
| | - Yuan Ji
- Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing, 100124, P.R. China. and Beijing Key Lab of Microstructure and Property of Advanced Material, Beijing University of Technology, Beijing, 100124, P.R. China
| | - Xiaodong Han
- Institute of Microstructure and Property of Advanced Materials, Beijing University of Technology, Beijing, 100124, P.R. China. and Beijing Key Lab of Microstructure and Property of Advanced Material, Beijing University of Technology, Beijing, 100124, P.R. China
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17
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Singh C, Panda E. Variation of electrical properties in thickening Al-doped ZnO films: role of defect chemistry. RSC Adv 2016. [DOI: 10.1039/c6ra06513a] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
This study addresses the variation in electrical properties in a thickening Al-doped ZnO (AZO) film up to 348 nm and correlates this with its defect chemistry.
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Affiliation(s)
- Chetan Singh
- Department of Materials Science and Engineering
- Indian Institute of Technology Gandhinagar
- India
| | - Emila Panda
- Department of Materials Science and Engineering
- Indian Institute of Technology Gandhinagar
- India
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18
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Li H, Zhang X, Liu N, Ding L, Tao J, Wang S, Su J, Li L, Gao Y. Enhanced photo-response properties of a single ZnO microwire photodetector by coupling effect between localized Schottky barriers and piezoelectric potential. OPTICS EXPRESS 2015; 23:21204-12. [PMID: 26367970 DOI: 10.1364/oe.23.021204] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
The coupling effect between localized Schottky barriers (SBs) and piezoelectric potential that impact the photo-response properties of a single ZnO microwire (MW) photodetector (PD) is studied. Localized SBs is introduced by Au NPs decoration. The negatively charged Au NPs deplete more carriers near the ZnO surface, which raises the SB height and sharply reduces the recover time of the PD from 142.4 s to 0.7 s. Moreover, after applying the compressive strain, the band structure of ZnO MW changes and piezoelectric potential generates, which further raises the SB height, thickens the depletion region and improves photo-response properties of the detector. The dark current is reduced by about 5 orders and its on/off current ratio increased by about 6 orders, which decreases the power consumption of the detector significantly. Under the above coupling effect between piezoelectric potential and localized SBs, the recover time of the detector is further reduced to 0.1 s ultimately. This work suggests that rational integration of localized SBs and piezoelectric potential is a viable approach to get ZnO MW PDs with high on/off ratio, ultrafast response speed and low power consumption.
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19
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Pu YC, Kibria MG, Mi Z, Zhang JZ. Ultrafast Exciton Dynamics in InGaN/GaN and Rh/Cr2O3 Nanoparticle-Decorated InGaN/GaN Nanowires. J Phys Chem Lett 2015; 6:2649-56. [PMID: 26266748 DOI: 10.1021/acs.jpclett.5b00909] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Ultrafast exciton and charge-carrier dynamics in InGaN/GaN nanowires (NWs) with and without Rh/Cr2O3 nanoparticle (NP) decoration have been investigated using femtosecond transient absorption (TA) techniques with excitation at 415 nm and white-light probe (450-700 nm). By comparing the TA profiles between InGaN/GaN and InGaN/GaN-Rh/Cr2O3 NWs, an additional decay component on the medium time scale (∼50 ps) was identified with Rh/Cr2O3 decoration, which is attributed to interfacial charge transfer from InGaN/GaN NWs to Rh/Cr2O3 NPs, desired for light energy conversion applications. This is consistent with reduced photoluminescence (PL) of the NWs by the Rh/Cr2O3 NPs. A kinetic model was developed to explain the TA results and gain further insight into the exciton and charge-carrier dynamics.
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Affiliation(s)
- Ying-Chih Pu
- †Department of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, California 95064, United States
| | - M G Kibria
- ‡Department of Electrical and Computer Engineering, McGill University, 3480 University Street, Montreal, Québec H3A 0E9, Canada
| | - Zetian Mi
- ‡Department of Electrical and Computer Engineering, McGill University, 3480 University Street, Montreal, Québec H3A 0E9, Canada
| | - Jin Z Zhang
- †Department of Chemistry and Biochemistry, University of California, 1156 High Street, Santa Cruz, California 95064, United States
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20
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Zhang F, Chao D, Cui H, Zhang W, Zhang W. Electronic Structure and Magnetism of Mn-Doped ZnO Nanowires. NANOMATERIALS (BASEL, SWITZERLAND) 2015; 5:885-894. [PMID: 28347042 PMCID: PMC5312896 DOI: 10.3390/nano5020885] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/10/2015] [Revised: 05/04/2015] [Accepted: 05/21/2015] [Indexed: 11/23/2022]
Abstract
The geometric structures, electronic and magnetic properties of Mn-doped ZnO nanowires were investigated using density functional theory. The results indicated that all the calculated energy differences were negative, and the energy of the ground state was 0.229 eV lower than ferromagnetic coupling, which show higher stability in antiferromagnetic coupling. The calculated results indicated that obvious spin splitting phenomenon occurred near the Femi level. The Zn atoms on the inner layer of ZnO nanowires are easily substituted by Mn atoms along the [0001] direction. It was also shown that the Mn2+-O2--Mn2+ magnetic coupling formed by intermediate O atom was proved to be caused by orbital hybridization between Mn 3d and O 2p states. The magnetic moments were mainly attributed to the unpaired Mn 3d orbitals, but not relevant with doping position of Mn atoms. Moreover, the optical properties of Mn-doped ZnO nanowires exhibited a novel blue-shifted optical absorption and enhanced ultraviolet-light emission. The above results show that the Mn-doped ZnO nanowires are a new type of magneto-optical materials with great promise.
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Affiliation(s)
- Fuchun Zhang
- College of Physics and Electronic Information, Yanan University, Yanan 716000, China.
| | - Dandan Chao
- College of Physics and Electronic Information, Yanan University, Yanan 716000, China.
| | - Hongwei Cui
- College of Physics and Electronic Information, Yanan University, Yanan 716000, China.
| | - Weihu Zhang
- College of Physics and Electronic Information, Yanan University, Yanan 716000, China.
| | - Weibin Zhang
- Department of Physics, Dongguk University, Seoul 100-715, Korea.
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21
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Macias-Montero M, Peláez RJ, Rico VJ, Saghi Z, Midgley P, Afonso CN, González-Elipe AR, Borras A. Laser treatment of Ag@ZnO nanorods as long-life-span SERS surfaces. ACS APPLIED MATERIALS & INTERFACES 2015; 7:2331-2339. [PMID: 25575182 DOI: 10.1021/am506622x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
UV nanosecond laser pulses have been used to produce a unique surface nanostructuration of Ag@ZnO supported nanorods (NRs). The NRs were fabricated by plasma enhanced chemical vapor deposition (PECVD) at low temperature applying a silver layer as promoter. The irradiation of these structures with single nanosecond pulses of an ArF laser produces the melting and reshaping of the end of the NRs that aggregate in the form of bundles terminated by melted ZnO spherical particles. Well-defined silver nanoparticles (NPs), formed by phase separation at the surface of these melted ZnO particles, give rise to a broad plasmonic response consistent with their anisotropic shape. Surface enhanced Raman scattering (SERS) in the as-prepared Ag@ZnO NRs arrays was proved by using a Rhodamine 6G (Rh6G) chromophore as standard analyte. The surface modifications induced by laser treatment improve the stability of this system as SERS substrate while preserving its activity.
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Affiliation(s)
- Manuel Macias-Montero
- Nanotechnology on Surfaces Laboratory, Materials Science Institute of Seville (ICMS), CSIC-University of Seville , C/AmericoVespucio 49, 41092 Seville, Spain
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22
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Taleb A, Mesguich F, Onfroy T, Yanpeng X. Design of TiO2/Au nanoparticle films with controlled crack formation and different architectures using a centrifugal strategy. RSC Adv 2015. [DOI: 10.1039/c4ra13829e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Centrifugal strategy is demonstrated to enable the design of hybrid nanocomposite films with controllable architecture, porosity, crack density and thickness.
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Affiliation(s)
- Abdelhafed Taleb
- Institut de Recherche de Chimie Paris
- CNRS – Chimie ParisTech
- 75005 Paris
- France
- Sorbonne Universités
| | - Frederic Mesguich
- Institut de Recherche de Chimie Paris
- CNRS – Chimie ParisTech
- 75005 Paris
- France
- Sorbonne Universités
| | - Thomas Onfroy
- Sorbonne Universités
- UPMC Univ Paris 06
- UMR 7197
- Laboratoire de Réactivité de Surface
- Paris
| | - Xue Yanpeng
- Institut de Recherche de Chimie Paris
- CNRS – Chimie ParisTech
- 75005 Paris
- France
- Sorbonne Universités
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23
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Udayabhaskar R, Karthikeyan B, Sreekanth P, Philip R. Enhanced multi-phonon Raman scattering and nonlinear optical power limiting in ZnO:Au nanostructures. RSC Adv 2015. [DOI: 10.1039/c4ra11204k] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Enhanced Raman scattering and nonlinear optical power limiting in ZnO:Au nanostructures is demonstrated.
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Affiliation(s)
- R. Udayabhaskar
- Department of Physics
- National Institute of Technology
- Tiruchirappalli 620 015
- India
| | - B. Karthikeyan
- Department of Physics
- National Institute of Technology
- Tiruchirappalli 620 015
- India
| | - P. Sreekanth
- Ultrafast and Nonlinear Optics Lab
- Light and Matter Physics Group
- Raman Research Institute
- Bangalore 560080
- India
| | - Reji Philip
- Ultrafast and Nonlinear Optics Lab
- Light and Matter Physics Group
- Raman Research Institute
- Bangalore 560080
- India
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24
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Hou X, Wang L. Controllable fabrication and photocatalysis of ZnO/Au nanohybrids via regenerative ion exchange and reduction cycles. RSC Adv 2014. [DOI: 10.1039/c4ra10785c] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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25
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Bayan S, Satpati B, Chakraborty P. ZnS nanoparticle decorated ZnO nanowall network: investigation through electron microscopy and secondary ion mass spectrometry. SURF INTERFACE ANAL 2014. [DOI: 10.1002/sia.5642] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Sayan Bayan
- Saha Institute of Nuclear Physics; Kolkata 700064 India
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26
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Bouzid H, Ali AM, Faisal M, Ismail AA. Germanium-catalyzed growth of zinc oxide nanorods by thermal evaporation for enhanced photonic efficiencies. ACTA ACUST UNITED AC 2014. [DOI: 10.1016/j.molcata.2014.03.009] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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27
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Han F, Yang S, Jing W, Jiang K, Jiang Z, Liu H, Li L. Surface plasmon enhanced photoluminescence of ZnO nanorods by capping reduced graphene oxide sheets. OPTICS EXPRESS 2014; 22:11436-11445. [PMID: 24921265 DOI: 10.1364/oe.22.011436] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
A hybrid structure of reduced graphene oxide (rGO) sheets/ZnO nanorods was prepared and its photoluminescence intensity ratio between the UV and defect emission was enhanced up to 14 times. By controlling the reduction degree of rGO on the surface of ZnO nanorods, the UV emission was tuned with the introduction of localized surface plasmons resonance of rGO sheets. The suppression of the defect emission was ascribed to the charge transfer and decreased with the distance between the rGO and ZnO nanorods.
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28
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Zhang J, Lai B, Chen Z, Chu S, Chu G, Peng R. Hexagonal core-shell and alloy Au/Ag nanodisks on ZnO nanorods and their optical enhancement effect. NANOSCALE RESEARCH LETTERS 2014; 9:237. [PMID: 24936157 PMCID: PMC4047434 DOI: 10.1186/1556-276x-9-237] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2014] [Accepted: 04/17/2014] [Indexed: 06/03/2023]
Abstract
Au and Ag hybrid hexagonal nanodisks were synthesized on ZnO nanorods' (0002) surface via a new two-step deposition-annealing method. The structural, compositional, as well as optical investigations were carried out systematically to find out the nanodisks' formation mechanism and optical enhancement effect. It was shown that the core-shell Au/Ag nanodisk can be formed under rapid annealing temperature of 500°C, while Au/Ag alloy nanodisks are formed if higher temperatures (>550°C) are applied. The optical effect from these nanodisks was studied through photoluminescence and absorption spectroscopy. It was found that the carrier-plasmon coupling together and carrier transfer between metal and ZnO contribute to the emission enhancement. Furthermore, the results suggest that the composition of nanodisk on the vicinity of metal/ZnO interface plays an important role in terms of the enhancement factors.
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Affiliation(s)
- Junming Zhang
- State Key Laboratory of Optoelectronic Materials and Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Boya Lai
- State Key Laboratory of Optoelectronic Materials and Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Zuxin Chen
- State Key Laboratory of Optoelectronic Materials and Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Sheng Chu
- State Key Laboratory of Optoelectronic Materials and Technology, Sun Yat-sen University, Guangzhou 510275, China
| | - Guang Chu
- School of Metallurgy Engineering, Central South University, Changsha 41008, China
| | - Rufang Peng
- School of Material Science and Engineering, Southwest University of Science and Technology, Mianyang615082, China
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29
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Yin XT, Que WX, Liao YL, Zhang J, Shen FY. Ag–ZnO composite nanocrystals: synthesis, characterisation and photocatalytic properties. ACTA ACUST UNITED AC 2013. [DOI: 10.1179/1433075x11y.0000000042] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
Affiliation(s)
- X T Yin
- Electronic Materials Research LaboratorySchool of Electronic and Information Engineering, Xi’ an Jiaotong University, Xi’an 710049, China
| | - W X Que
- Electronic Materials Research LaboratorySchool of Electronic and Information Engineering, Xi’ an Jiaotong University, Xi’an 710049, China
| | - Y L Liao
- Electronic Materials Research LaboratorySchool of Electronic and Information Engineering, Xi’ an Jiaotong University, Xi’an 710049, China
| | - J Zhang
- Electronic Materials Research LaboratorySchool of Electronic and Information Engineering, Xi’ an Jiaotong University, Xi’an 710049, China
| | - F Y Shen
- Electronic Materials Research LaboratorySchool of Electronic and Information Engineering, Xi’ an Jiaotong University, Xi’an 710049, China
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30
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Chan NY, Zhao M, Wang N, Au K, Wang J, Chan LWH, Dai J. Palladium nanoparticle enhanced giant photoresponse at LaAlO3/SrTiO3 two-dimensional electron gas heterostructures. ACS NANO 2013; 7:8673-8679. [PMID: 24003972 DOI: 10.1021/nn4029184] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
With LaAlO3 surface modification by Pd nanoparticles, LaAlO3/SrTiO3 (LAO/STO) interfacial two-dimensional electron gas presents a giant optical switching effect with a photoconductivity on/off ratio as high as 750% under UV light irradiation. Pd nanoparticles with a size around 2 nm are deposited on top of the LAO surface, and the LAO/STO interface exhibits a giant response to UV light with a wavelength shorter than 400 nm. This giant optical switching behavior has been explained by the Pd nanoparticle's catalytic effect and surface/interface charge coupling.
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Affiliation(s)
- Ngai Yui Chan
- Department of Applied Physics, The Hong Kong Polytechnic University , Hung Hom, Kowloon, Hong Kong, People's Republic of China
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31
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Huang C, Dong W, Zhang K, Zou J, Zhang Y, Wei T, Sun Y, Chen X, Dai N. Radial sandwich hybrid nanorods by analogously inserting Au nanoparticles in ZnO nanorods. RSC Adv 2013. [DOI: 10.1039/c3ra44351e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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32
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Kochuveedu ST, Jang YH, Kim DH. A study on the mechanism for the interaction of light with noble metal-metal oxide semiconductor nanostructures for various photophysical applications. Chem Soc Rev 2013; 42:8467-93. [DOI: 10.1039/c3cs60043b] [Citation(s) in RCA: 447] [Impact Index Per Article: 40.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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33
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Wang L, Yue Q, Li H, Xu S, Guo L, Zhang X, Wang H, Gao X, Wang W, Liu J, Liu P. Facet-dependent electrochemiluminescence spectrum of nanostructured ZnO. Sci China Chem 2012. [DOI: 10.1007/s11426-012-4703-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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34
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Surface-Plasmon-Enhanced Band Emission of ZnO Nanoflowers Decorated with Au Nanoparticles. Chemistry 2012; 18:7467-72. [DOI: 10.1002/chem.201200054] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Indexed: 11/07/2022]
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35
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Goñi AR, Güell F, Pérez LA, López-Vidrier J, Ossó JO, Coronado EA, Morante JR. Retrieving the spatial distribution of cavity modes in dielectric resonators by near-field imaging and electrodynamics simulations. NANOSCALE 2012; 4:1620-1626. [PMID: 22286103 DOI: 10.1039/c2nr11693f] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
For good performance of photonic devices whose working principle is based on the enhancement of electromagnetic fields obtained by confining light into dielectric resonators with dimensions in the nanometre length scale, a detailed knowledge of the optical mode structure becomes essential. However, this information is usually lacking and can only be indirectly obtained by conventional spectroscopic techniques. Here we unraveled the influence of wire size, incident wavelength, degree of polarization and the presence of a substrate on the optical near fields generated by cavity modes of individual hexagonal ZnO nanowires by combining scanning near-field optical microscopy (SNOM) with electrodynamics calculations within the discrete dipole approximation (DDA). The near-field patterns obtained with very high spatial resolution, better than 50 nm, exhibit striking size and spatial-dispersion effects, which are well accounted for within DDA, using a wavevector-dependent dipolar interaction and considering the dielectric anisotropy of ZnO. Our results show that both SNOM and DDA simulations are powerful tools for the design of optoelectronic devices able to manipulate light at the nanoscale.
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Affiliation(s)
- Alejandro R Goñi
- ICREA & Institut de Ciència de Materials de Barcelona (ICMAB-CSIC), Esfera UAB, E-08193, Bellaterra, Spain.
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36
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Tian Y, Bakaul SR, Wu T. Oxide nanowires for spintronics: materials and devices. NANOSCALE 2012; 4:1529-1540. [PMID: 22293913 DOI: 10.1039/c2nr11767c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Spintronics, or spin-based data storage and manipulation technology, is emerging as a very active research area because of both new science and potential technological applications. As the characteristic lengths of spin-related phenomena naturally fall into the nanometre regime, researchers start applying the techniques of bottom-up nanomaterial synthesis and assembly to spintronics. It is envisaged that novel physics regarding spin manipulation and domain dynamics can be realized in quantum confined nanowire-based devices. Here we review the recent breakthroughs related to the applications of oxide nanowires in spintronics from the perspectives of both material candidates and device fabrication. Oxide nanowires generally show excellent crystalline quality and tunable physical properties, but more efforts are imperative as we strive to develop novel spintronic nanowires and devices.
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Affiliation(s)
- Yufeng Tian
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, 637371, Singapore
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37
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Yin J, Zang Y, Yue C, Wu Z, Wu S, Li J, Wu Z. Ag nanoparticle/ZnO hollow nanosphere arrays: large scale synthesis and surface plasmon resonance effect induced Raman scattering enhancement. ACTA ACUST UNITED AC 2012. [DOI: 10.1039/c2jm16003j] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
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38
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Shen X, Chen L, Li D, Zhu L, Wang H, Liu C, Wang Y, Xiong Q, Chen H. Assembly of colloidal nanoparticles directed by the microstructures of polycrystalline ice. ACS NANO 2011; 5:8426-8433. [PMID: 21942743 DOI: 10.1021/nn203399z] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We show that the microstructures of polycrystalline ice can serve as a confining template for one-dimensional assembly of colloidal nanoparticles. Upon simply freezing an aqueous colloid, the nanoparticles are excluded from ice grains and form chains in the ice veins. The nanoparticle chains are transferable and can be strengthened by polymer encapsulation. After coating with polyaniline shells, simple sedimentation is used to remove large aggregates, enriching single-line chains of 40 nm gold nanoparticles with a total length of several micrometers. When gold nanorods were used, they formed one-dimensional aggregates with specific end-to-end conformation, indicating the confining effects of the nanoscale ice veins at the final stage of freezing. The unbranched and ultralong plasmonic chains are of importance for future study of plasmonic coupling and development of plasmonic waveguides.
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Affiliation(s)
- Xiaoshuang Shen
- Division of Chemistry and Biological Chemistry, Nanyang Technological University, Singapore 637371
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39
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Xing G, Wang D, Yao B, Lloyd Foong Nien A, Yan Y. Structural characteristics, low threshold ultraviolet lasing and ultrafast carrier dynamics in high crystalline ZnO nanowire arrays. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.09.007] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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40
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Li GP, Chen R, Guo DL, Wong LM, Wang SJ, Sun HD, Wu T. Nanoscale semiconductor-insulator-metal core/shell heterostructures: facile synthesis and light emission. NANOSCALE 2011; 3:3170-3177. [PMID: 21698326 DOI: 10.1039/c1nr10352k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Controllably constructing hierarchical nanostructures with distinct components and designed architectures is an important theme of research in nanoscience, entailing novel but reliable approaches of bottom-up synthesis. Here, we report a facile method to reproducibly create semiconductor-insulator-metal core/shell nanostructures, which involves first coating uniform MgO shells onto metal oxide nanostructures in solution and then decorating them with Au nanoparticles. The semiconductor nanowire core can be almost any material and, herein, ZnO, SnO(2) and In(2)O(3) are used as examples. We also show that linear chains of short ZnO nanorods embedded in MgO nanotubes and porous MgO nanotubes can be obtained by taking advantage of the reduced thermal stability of the ZnO core. Furthermore, after MgO shell-coating and the appropriate annealing treatment, the intensity of the ZnO near-band-edge UV emission becomes much stronger, showing a 25-fold enhancement. The intensity ratio of the UV/visible emission can be increased further by decorating the surface of the ZnO/MgO nanowires with high-density plasmonic Au nanoparticles. These heterostructured semiconductor-insulator-metal nanowires with tailored morphologies and enhanced functionalities have great potential for use as nanoscale building blocks in photonic and electronic applications.
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Affiliation(s)
- Gong Ping Li
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371
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41
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Bera A, Basak D. Pd-nanoparticle-decorated ZnO nanowires: ultraviolet photosensitivity and photoluminescence properties. NANOTECHNOLOGY 2011; 22:265501. [PMID: 21576786 DOI: 10.1088/0957-4484/22/26/265501] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
ZnO nanowires (NWs) have been decorated with Pd nanoparticles of sizes less than 10 nm (Pd-ZnO NWs) via a chemical solution route. The microstructural characterizations have been done using field emission scanning electron and high-resolution transmission electron microscopes. The effects of attaching Pd nanoparticles to the walls of ZnO NWs have been investigated by studying the ultraviolet (UV) photosensitivity and photoluminescence (PL) properties. The surface-modified NWs show a UV photosensitivity more than double and a response seven times faster compared to the bare NWs. The photocarrier relaxation under the steady UV illumination condition is quite different in Pd-ZnO NWs. The higher and faster photosensitivity has been explained on the basis of photocarrier transfer from the conduction band of ZnO to the Fermi level of Pd and subsequent electron trapping by the adsorbed O(2) molecules on the NWs' surface, which have been presented through a proposed model. The PL spectrum of Pd-ZnO NWs shows that the intensities of the band-edge and defect-related emissions decrease and increase, respectively, due to Pd anchoring, the effect being pronounced as the density of Pd nanoparticles increases.
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Affiliation(s)
- Ashok Bera
- Department of Solid State Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
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Jang YH, Yang SY, Jang YJ, Park C, Kim JK, Kim DH. Ultrahigh Density Arrays of Toroidal ZnO Nanostructures by One-Step Cooperative Self-Assembly Processes: Mechanism of Structural Evolution and Hybridization with Au Nanoparticles. Chemistry 2011; 17:2068-76. [DOI: 10.1002/chem.201002912] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2010] [Indexed: 11/06/2022]
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43
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Ahmad M, Yingying S, Nisar A, Sun H, Shen W, Wei M, Zhu J. Synthesis of hierarchical flower-like ZnO nanostructures and their functionalization by Au nanoparticles for improved photocatalytic and high performance Li-ion battery anodes. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c1jm10720h] [Citation(s) in RCA: 340] [Impact Index Per Article: 26.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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44
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Ordered dispersion of ZnO quantum dots in SiO2 matrix and its strong emission properties. J Colloid Interface Sci 2011; 353:30-8. [DOI: 10.1016/j.jcis.2010.09.055] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2010] [Revised: 09/15/2010] [Accepted: 09/18/2010] [Indexed: 11/22/2022]
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45
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Ruankham P, Sagawa T, Sakaguchi H, Yoshikawa S. Vertically aligned ZnO nanorods doped with lithium for polymer solar cells: defect related photovoltaic properties. ACTA ACUST UNITED AC 2011. [DOI: 10.1039/c0jm04452k] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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46
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Bera A, Ghosh T, Basak D. Enhanced photoluminescence and photoconductivity of ZnO nanowires with sputtered Zn. ACS APPLIED MATERIALS & INTERFACES 2010; 2:2898-2903. [PMID: 20919682 DOI: 10.1021/am1006047] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
We have sputtered Zn onto quasi-one-dimensional ZnO nanowires (NWs) in order to investigate the effect of Zn diffusion on the photoluminescence and photoconduction properties of ZnO NWs. Elemental mapping clearly indicates higher Zn concentration in the NWs due to diffusion of Zn. The Zn-sputtered NWs show an enhanced ultraviolet emission with 7 nm red shift. Since the ionization energy of Zni is 51 meV, the enhanced PL emission with a red shift is correlated to the coupling between free exciton and zinc interstitials (Zni) defects. The photocurrent transients show almost 20 times more photocurrent generation in Zn/ZnO NWs compared to the as-grown NWs. In contrast, the thin film shows no significant change in the photoluminescence and photoconductivity. Based on the photoconductivity and photoluminescence results, we predict that Zn diffusion in the NWs occurs easily compared to the films because of the smaller dimensions of the NWs.
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Affiliation(s)
- A Bera
- Department of Solid State Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
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47
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Zhang Y, Xu J, Xu P, Zhu Y, Chen X, Yu W. Decoration of ZnO nanowires with Pt nanoparticles and their improved gas sensing and photocatalytic performance. NANOTECHNOLOGY 2010; 21:285501. [PMID: 20562475 DOI: 10.1088/0957-4484/21/28/285501] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Pt nanoparticles were introduced on the surface of ZnO nanowires using a chemically driven self-assembly method. Through this controllable method, Pt-nanoparticle-functionalized ZnO nanowires (Pt NPs-ZnO NWs) with uniform particle dispersion, tunable Pt particle sizes, and narrow particle size distribution were obtained. Changes in the morphology of the decorative preparation were observed as the amount of linker reagent and the concentration of Pt nanoparticle solution were altered. The as-prepared Pt NPs-ZnO NWs with optimal morphology showed excellent gas sensing and photocatalytic performance. Tuning of the functionalities of photocatalytic and gas sensors can be obtained by tailoring the morphology of Pt NP-ZnO NW composite materials.
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Affiliation(s)
- Yuan Zhang
- Department of Chemistry, College of Science, Shanghai University, Shanghai 200444, People's Republic of China
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48
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Dev A, Niepelt R, Richters JP, Ronning C, Voss T. Stable enhancement of near-band-edge emission of ZnO nanowires by hydrogen incorporation. NANOTECHNOLOGY 2010; 21:065709. [PMID: 20057023 DOI: 10.1088/0957-4484/21/6/065709] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
We report on the photoluminescence properties of ZnO nanowires treated with a mild Ar plasma. The nanowires exhibited stable and strong enhancement of the near-band-edge emission and quenching of the deep level emission. The low temperature PL revealed a strong hydrogen donor-bound-exciton line in the plasma-treated samples indicating unintentional incorporation of hydrogen during the plasma treatment. To confirm the results, hydrogen was implanted into the ZnO nanowires with a low ion energy of 600 eV and different fluences. The observed result can be related to the passivation of deep centers by hydrogen. The absolute photoluminescence intensity measured by an integrating sphere showed stable and strong UV emission from the treated samples even after several weeks.
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Affiliation(s)
- A Dev
- Institute of Solid State Physics, University of Bremen, Bremen, Germany.
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49
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Bera A, Basak D. Photoluminescence and photoconductivity of ZnS-coated ZnO nanowires. ACS APPLIED MATERIALS & INTERFACES 2010; 2:408-12. [PMID: 20356186 DOI: 10.1021/am900686c] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
ZnO nanowires (NWs) with a ZnS coating are synthesized in order to modify the surface without changing the diameter of the NWs. They have the wurtzite ZnO at the core and a cubic ZnS at the outer layer. The NWs show a sharp ultraviolet and a broad visible emission of the photoluminescence spectra. Surface modification has led to a change in the position of the maxima of the visible emission in ZnO-ZnS NWs. The photocarrier relaxation under steady UV illumination occurs in ZnO NW arrays but is absent in ZnO-ZnS NW arrays. The dark current value for both type of NWs are similar, whereas the photocurrent value is much higher in the surface-modified NWs. Higher photocurrent value indicates a transport of the photogenerated carriers from the ZnS layer to ZnO during UV illumination. The carrier transport mechanism is proposed through a model.
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Affiliation(s)
- Ashok Bera
- Department of Solid State Physics, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India
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50
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Cheng B, Jiao J, Sun W, Tian B, Xiao Y, Lei S. Lattice variation and Raman spectroscopy in hierarchical heterostructures of zinc antimonate nanoislands on ZnO nanobelts. NANOTECHNOLOGY 2010; 21:025704. [PMID: 19955602 DOI: 10.1088/0957-4484/21/2/025704] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
In ZnO hierarchical heterostructures of zinc antimonate nanoislands on ZnO nanobelts, the substitution of Sb(5+) for Zn(2+) induces lattice contraction and a variation in vacancy defects, and moreover the preferential accumulation and segregation of Sb in [001] planes results in the intense perturbation of atomic motion in the a-b plane. Under nonresonant conditions, nonpolar E(2)(high) and polar quasi-longitudinal optic (LO) modes decrease in frequency due to finite-size and phonon confinement effects. Under resonant conditions, localized excitons can ionize to free carriers and form plasmons at higher excitation power density, resulting in the transformation of scattering coupling from localized exciton-LO-phonon to LO-phonon-plasmon. The intensity ratio of 2LO/1LO decreases and multiphonon scattering shows a decrease in frequency with unequal neighboring interval, and moreover the scattering coupling between the continuum of electron-hole plasmon and the discrete LO phonons causes an asymmetric lineshape.
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Affiliation(s)
- Baochang Cheng
- Institute for Advanced Studying, School of Materials Science and Engineering, Nanchang University, Nanchang, People's Republic of China.
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