The Experts below are selected from a list of 32124 Experts worldwide ranked by ideXlab platform
Sang W. Joo - One of the best experts on this subject based on the ideXlab platform.
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conductivity inversion of zno nanoparticles in zno carbon nanofiber hybrid thin film devices by surfactant assisted c doping and non rectifying non linear electrical properties via interfacial trap induced tunneling for stress grading applications
Journal of Applied Physics, 2019Co-Authors: G.r. Dillip, Arghya Narayan Banerjee, Sang W. JooAbstract:A special nonrectifying, nonlinear current–voltage characteristic is observed in ZnO nanoparticle-anchored carbon nanofiber (ZnO-CNF) hybrid thin film devices, which has interesting applications in nonlinear stress-grading materials for high-voltage devices and overvoltage protectors in multifunctional electronic circuits. A simple chemical precipitation method is used to fabricate the hybrid films, followed by vacuum annealing at elevated temperatures. Interestingly, the organic surfactant (Triton X-114), used as a binder during the film deposition, manifests unintentional carbon doping into a ZnO lattice, which leads to a conductivity inversion of ZnO from n-type in the lower temperature (300 °C) annealed hybrid into p-type in the higher temperature (600 °C) annealed film. Electrical characterizations reveal that the CNF-ZnO interfaces act as a Metal-Semiconductor Junction with low barrier height, leading to nonrectifying Junction properties. Also, the surfactant-induced C-atoms create trap states at the interface which “emit” the trapped charges via interfacial field-assisted tunneling, thus imposing nonlinearity (in both forward and reverse directions) on the I–V curves.
G.r. Dillip - One of the best experts on this subject based on the ideXlab platform.
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conductivity inversion of zno nanoparticles in zno carbon nanofiber hybrid thin film devices by surfactant assisted c doping and non rectifying non linear electrical properties via interfacial trap induced tunneling for stress grading applications
Journal of Applied Physics, 2019Co-Authors: G.r. Dillip, Arghya Narayan Banerjee, Sang W. JooAbstract:A special nonrectifying, nonlinear current–voltage characteristic is observed in ZnO nanoparticle-anchored carbon nanofiber (ZnO-CNF) hybrid thin film devices, which has interesting applications in nonlinear stress-grading materials for high-voltage devices and overvoltage protectors in multifunctional electronic circuits. A simple chemical precipitation method is used to fabricate the hybrid films, followed by vacuum annealing at elevated temperatures. Interestingly, the organic surfactant (Triton X-114), used as a binder during the film deposition, manifests unintentional carbon doping into a ZnO lattice, which leads to a conductivity inversion of ZnO from n-type in the lower temperature (300 °C) annealed hybrid into p-type in the higher temperature (600 °C) annealed film. Electrical characterizations reveal that the CNF-ZnO interfaces act as a Metal-Semiconductor Junction with low barrier height, leading to nonrectifying Junction properties. Also, the surfactant-induced C-atoms create trap states at the interface which “emit” the trapped charges via interfacial field-assisted tunneling, thus imposing nonlinearity (in both forward and reverse directions) on the I–V curves.
Jing Tang - One of the best experts on this subject based on the ideXlab platform.
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A photovoltaic device structure based on internal electron emission
Nature, 2003Co-Authors: Eric W. Mcfarland, Jing TangAbstract:There has been an active search for cost-effective photovoltaic devices since the development of the first solar cells in the 1950s (refs 1–3 ). In conventional solid-state solar cells, electron–hole pairs are created by light absorption in a semiconductor, with charge separation and collection accomplished under the influence of electric fields within the semiconductor. Here we report a multilayer photovoltaic device structure in which photon absorption instead occurs in photoreceptors deposited on the surface of an ultrathin metal–semiconductor Junction Schottky diode. Photoexcited electrons are transferred to the metal and travel ballistically to—and over—the Schottky barrier, so providing the photocurrent output. Low-energy (∼1 eV) electrons have surprisingly long ballistic path lengths in noble metals^ 4 , 5 , allowing a large fraction of the electrons to be collected. Unlike conventional cells, the semiconductor in this device serves only for majority charge transport and separation. Devices fabricated using a fluorescein photoreceptor on an Au/TiO_2/Ti multilayer structure had typical open-circuit photovoltages of 600–800 mV and short-circuit photocurrents of 10–18 µA cm^-2 under 100 mW cm^-2 visible band illumination: the internal quantum efficiency (electrons measured per photon absorbed) was 10 per cent. This alternative approach to photovoltaic energy conversion might provide the basis for durable low-cost solar cells using a variety of materials.
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a photovoltaic device structure based on internal electron emission
Nature, 2003Co-Authors: Eric W. Mcfarland, Jing TangAbstract:There has been an active search for cost-effective photovoltaic devices since the development of the first solar cells in the 1950s (refs 1-3). In conventional solid-state solar cells, electron-hole pairs are created by light absorption in a semiconductor, with charge separation and collection accomplished under the influence of electric fields within the semiconductor. Here we report a multilayer photovoltaic device structure in which photon absorption instead occurs in photoreceptors deposited on the surface of an ultrathin Metal-Semiconductor Junction Schottky diode. Photoexcited electrons are transferred to the metal and travel ballistically to--and over--the Schottky barrier, so providing the photocurrent output. Low-energy (approximately 1 eV) electrons have surprisingly long ballistic path lengths in noble metals, allowing a large fraction of the electrons to be collected. Unlike conventional cells, the semiconductor in this device serves only for majority charge transport and separation. Devices fabricated using a fluorescein photoreceptor on an Au/TiO2/Ti multilayer structure had typical open-circuit photovoltages of 600-800 mV and short-circuit photocurrents of 10-18 micro A cm(-2) under 100 mW cm(-2) visible band illumination: the internal quantum efficiency (electrons measured per photon absorbed) was 10 per cent. This alternative approach to photovoltaic energy conversion might provide the basis for durable low-cost solar cells using a variety of materials.
Arghya Narayan Banerjee - One of the best experts on this subject based on the ideXlab platform.
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conductivity inversion of zno nanoparticles in zno carbon nanofiber hybrid thin film devices by surfactant assisted c doping and non rectifying non linear electrical properties via interfacial trap induced tunneling for stress grading applications
Journal of Applied Physics, 2019Co-Authors: G.r. Dillip, Arghya Narayan Banerjee, Sang W. JooAbstract:A special nonrectifying, nonlinear current–voltage characteristic is observed in ZnO nanoparticle-anchored carbon nanofiber (ZnO-CNF) hybrid thin film devices, which has interesting applications in nonlinear stress-grading materials for high-voltage devices and overvoltage protectors in multifunctional electronic circuits. A simple chemical precipitation method is used to fabricate the hybrid films, followed by vacuum annealing at elevated temperatures. Interestingly, the organic surfactant (Triton X-114), used as a binder during the film deposition, manifests unintentional carbon doping into a ZnO lattice, which leads to a conductivity inversion of ZnO from n-type in the lower temperature (300 °C) annealed hybrid into p-type in the higher temperature (600 °C) annealed film. Electrical characterizations reveal that the CNF-ZnO interfaces act as a Metal-Semiconductor Junction with low barrier height, leading to nonrectifying Junction properties. Also, the surfactant-induced C-atoms create trap states at the interface which “emit” the trapped charges via interfacial field-assisted tunneling, thus imposing nonlinearity (in both forward and reverse directions) on the I–V curves.
Zhong Lin Wang - One of the best experts on this subject based on the ideXlab platform.
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influence of external electric field on piezotronic effect in zno nanowires
Nano Research, 2015Co-Authors: Fei Xue, Limin Zhang, Xiaolong Feng, Fengru Fan, Xiaonan Wen, Li Zheng, Zhong Lin WangAbstract:In this work, the piezotronic effect is investigated for the first time in external electric fields ranging from 0 V·cm–1 to 2,000 V·cm–1 by using n-type ZnO nanowires supported by a flexible substrate. In the presence of an external electric field, the Schottky barrier height (SBH) is lowered by the image force, allowing more free carriers to pass through the Metal-Semiconductor Junction and enhancing the screening effect on positive piezoelectric polarization charges. As the strength of the external electric field increases, the piezotronic effect is significantly suppressed and the Metal-Semiconductor contact finally exhibits Ohmic behavior. The experimental results show that devices can be classified into three groups, corresponding to low, moderate, and high carrier densities of the nanowires used. This work not only helps us to explicate the basic physical mechanism of the piezotronic effect in a harsh environment in an electric field but also provides guidelines for future design and fabrication of piezotronic devices.