Cu-Deficiency in the p-Type Semiconductor Cu5–xTa11O30: Impact on Its Crystalline Structure, Surfaces, and Photoelectrochemical Properties

2014 ◽  
Vol 26 (23) ◽  
pp. 6711-6721 ◽  
Author(s):  
Ian Sullivan ◽  
Prangya P. Sahoo ◽  
Lindsay Fuoco ◽  
Andrew S. Hewitt ◽  
Sean Stuart ◽  
...  
Keyword(s):  
Crystalline Structure ◽  
Photoelectrochemical Properties ◽  
Cu Deficiency ◽  
Type Semiconductor ◽  
P Type

scholarly journals A Metastable p-Type Semiconductor as a Defect-Tolerant Photoelectrode

Molecules ◽  
2021 ◽  
Vol 26 (22) ◽  
pp. 6830
Author(s):  
Zahirul Sohag ◽  
Shaun O’Donnell ◽  
Lindsay Fuoco ◽  
Paul A. Maggard
Keyword(s):  
Valence Band ◽  
Crystalline Structure ◽  
Surface Oxidation ◽  
Defect Tolerance ◽  
Defect States ◽  
Powder Density ◽  
Type Semiconductor ◽  
Recombination Centers ◽  
Gap States ◽  
P Type

A p-type Cu3Ta7O19 semiconductor was synthesized using a CuCl flux-based approach and investigated for its crystalline structure and photoelectrochemical properties. The semiconductor was found to be metastable, i.e., thermodynamically unstable, and to slowly oxidize at its surfaces upon heating in air, yielding CuO as nano-sized islands. However, the bulk crystalline structure was maintained, with up to 50% Cu(I)-vacancies and a concomitant oxidation of the Cu(I) to Cu(II) cations within the structure. Thermogravimetric and magnetic susceptibility measurements showed the formation of increasing amounts of Cu(II) cations, according to the following reaction: Cu3Ta7O19 + x/2 O2 → Cu(3−x)Ta7O19 + x CuO (surface) (x = 0 to ~0.8). With minor amounts of surface oxidation, the cathodic photocurrents of the polycrystalline films increase significantly, from <0.1 mA cm−2 up to >0.5 mA cm−2, under visible-light irradiation (pH = 6.3; irradiant powder density of ~500 mW cm−2) at an applied bias of −0.6 V vs. SCE. Electronic structure calculations revealed that its defect tolerance arises from the antibonding nature of its valence band edge, with the formation of defect states in resonance with the valence band, rather than as mid-gap states that function as recombination centers. Thus, the metastable Cu(I)-containing semiconductor was demonstrated to possess a high defect tolerance, which facilitates its high cathodic photocurrents.

Annealing effect on the optical and photoelectrochemical properties of lead oxide

2018 ◽  
Vol 84 (3) ◽  
pp. 30301 ◽  
Author(s):  
Wided Zerguine ◽  
Djamila Abdi ◽  
Farid Habelhames ◽  
Meriem Lakhdari ◽  
Hassina Derbal-Habak ◽  
...  
Keyword(s):  
Lead Oxide ◽  
Orthorhombic Phase ◽  
Heat Treatments ◽  
Photoelectrochemical Properties ◽  
X Ray Diffraction ◽  
Vis Spectroscopy ◽  
Size And Morphology ◽  
Two Phases ◽  
P Type ◽  
The Relationship

Effect of the annealing oxidation time of electrodeposited lead (Pb) on the phase formation of lead oxide (PbO) films is reported. The phase structure, optical properties, size and morphology of the films were investigated by scanning electron microscopy, X-ray diffraction and UV-vis spectroscopy. The relationship between structur and photoelectrochemical properties was investigated. Thin films of PbO produced via air annealing of electrodeposited lead consist of a mixture of two phases, orthorhombic (o-PbO) and tetragonal (t-PbO), that determine the material properties and effectiveness as absorber layer in a photoelectrochemical device. The proportion of tetragonal t-PbO increases for longer heat treatments. After 40 h, the sample consists mainly of tetragonal t-PbO. The p-type semiconducting behavior of lead oxide was studied by photocurrent measurements. Different heat treatments yield variations in the ratio of tetragonal to orthorhombic lead oxide that effect on device performances, where devices with a higher content of tetragonal t-PbO show higher photocurrent than with the orthorhombic phase.

Transparent P-type Conducting LaCuOS Layered Oxysulfide

2001 ◽  
Vol 666 ◽  
Author(s):  
Kazushige Ueda ◽  
Shin-ichiro Inoue ◽  
Sakyo Hirose ◽  
Hiroshi Kawazoe ◽  
Hideo Hosono
Keyword(s):  
Electrical Conductivity ◽  
Visible Region ◽  
Optoelectronic Devices ◽  
Promising Material ◽  
High Transparency ◽  
Conducting Oxides ◽  
Excitonic Absorption ◽  
Type Semiconductor ◽  
Optical Applications ◽  
P Type

ABSTRACTMaterials design for transparent p-type conducting oxides was extended to oxysulfide system. LaCuOS was selected as a candidate for a transparent p-type semiconductor. It was found that the electrical conductivity of LaCuOS was p-type and controllable from semiconducting to semi-metallic states by substituting Sr2+ for La3+. LaCuOS films showed high transparency in the visible region, and the bandgap estimated was approximately 3.1 eV. Moreover, it was revealed that LaCuOS showed sharp excitonic absorption and emission at the bandgap edge, which is advantageous for optical applications. A layered oxysulfide, LaCuOS, was proposed to be a promising material for optoelectronic devices.

The Study of p-n and Schottky Junction for Magnetodiode

2011 ◽  
Vol 378-379 ◽  
pp. 663-667 ◽  
Author(s):  
Toempong Phetchakul ◽  
Wittaya Luanatikomkul ◽  
Chana Leepattarapongpan ◽  
E. Chaowicharat ◽  
Putapon Pengpad ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Electrical Properties ◽  
Simulation Model ◽  
Hall Effect ◽  
Schottky Junction ◽  
Field Sensitivity ◽  
Field Response ◽  
Type Semiconductor ◽  
Simulation Results ◽  
P Type

This paper presents the simulation model of Dual Magnetodiode and Dual Schottky Magnetodiode using Sentaurus TCAD to simulate the virtual structure of magneto device and apply Hall Effect to measure magnetic field response of the device. Firstly, we use the program to simulate the magnetodiode with p-type semiconductor and aluminum anode and measure electrical properties and magnetic field sensitivity. Simulation results show that sensitivity of Dual Schottky magnetodiode is higher than that of Dual magnetodiode.

Study on Phases and Thermoelectric Properties of Bulk Fe4Sb12 and Fe3CoSb12 Prepared by Milling and Sintering

2011 ◽  
Vol 121-126 ◽  
pp. 1526-1529
Author(s):  
Ke Gao Liu ◽  
Jing Li
Keyword(s):  
Thermoelectric Properties ◽  
Impurity Phase ◽  
Semiconductor Materials ◽  
Thermal Constant ◽  
X Ray Diffraction ◽  
X Ray ◽  
Seebeck Coefficients ◽  
Maximum Value ◽  
Type Semiconductor ◽  
P Type

Bulk Fe4Sb12 and Fe3CoSb12 were prepared by sintering at 600 °C. The phases of samples were analyzed by X-ray diffraction and their thermoelectric properties were tested by electric constant instrument and laser thermal constant instrument. Experimental results show that, the major phases of bulk samples are skutterudite with impurity phase FeSb2. The electric resistivities of the samples increase with temperature rising at 100~500 °C. The bulk samples are P-type semiconductor materials. The Seebeck coefficients of the bulk Fe4Sb12 are higher than those of bulk Fe3CoSb12 samples at 100~200 °C but lower at 300~500 °C. The power factor of the bulk Fe4Sb12 samples decreases with temperature rising while that of bulk Fe3CoSb12 samples increases with temperature rising at 100~500 °C. The thermal conductivities of the bulk Fe4Sb12 samples are relatively higher than those of and Fe3CoSb12, which maximum value is up to 0.0974 Wm-1K-1. The ZT value of bulk Fe3CoSb12 increases with temperature rising at 100~500 °C, the maximum value is up to 0.031.The ZT values of the bulk Fe4Sb12 samples are higher than those of bulk Fe3CoSb12 at 100~300 °C while lower at 400~500 °C.

A NOx Sensor Based on Solid-Electrolyte Impedance Transducer

2008 ◽  
Vol 47-50 ◽  
pp. 479-482 ◽  
Author(s):  
Youichi Shimizu ◽  
Satoko Takase ◽  
Daisuke Koba
Keyword(s):  
Solid Electrolyte ◽  
Selective Detection ◽  
Ceramic Oxides ◽  
Sensing Mechanism ◽  
Sensor Device ◽  
Nox Sensor ◽  
Type Semiconductor ◽  
Ionic Solid ◽  
P Type ◽  
Perovskite Type

A new solid-electrolyte impedance-metric NOx sensor device composed of a lithium ionic solid electrolyte: Li1.5Al0.5Ti1.5(PO4)3 (LATP) as a transducer and ceramic oxides (perovskite-type oxides, TiO2, SnO2, etc) as a receptor, respectively, have been systematically investigated for the detection of NOx (NO and NO2 ) in the range 10 – 200 ppm at 400 - 500°C. Responses of the sensors were able to divide component between resistance and capacitance, and it was found that the device was applicable to the selective detection of NO or NO2 concentration in each ingredient. Especially, those using TiO2, SnO2 (n-type semiconductor) and perovskite-type oxides (LaCoO3, LaNiO3 and LaCrO3) based receptors gave good responses to NO and NO2. It was also found that the responses were different between n-type or p-type semiconductors, in which we tried to elucidate the sensing mechanism

Photoelectrochemical properties of CdSe quantum dot sensitized p-type flower-like NiO solar cells with different deposition layer

2016 ◽  
Vol 84 ◽  
pp. 212-217 ◽  
Author(s):  
Xiaowei Li ◽  
Ruixue Chen ◽  
Huidong Sui ◽  
Xiaoxian Yuan ◽  
Meng Li ◽  
...  
Keyword(s):  
Solar Cells ◽  
Quantum Dot ◽  
Photoelectrochemical Properties ◽  
Cdse Quantum Dot ◽  
P Type
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