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101.
102.
Semiconducting properties of oxide film grown over PbIn binary alloy electrodes in alkaline medium is elucidated. It has been observed that anodic film formed over Pb0.3 wt%In alloy in the potential range of −0.75 to 1.25 V (vs. Hg/HgO) shows better short circuit photocurrent density (3.2 mA/cm2) than the oxide film over pure Pb electrode (2.2 mA/cm2). The observed photoactivity is correlated with the interfacial parameters of the nonstoichiometric oxide–electrolyte interface using Gartner Butler model. Effect of varying concentration of In dopant in the PbO matrix on the interfacial properties is reported. It is shown that combined effect of space charge width and diffusion length of the minority carriers can describe the observed photoactivity efficiently. 相似文献
103.
Y. M. Yang A. Yu B. Hsu W. C. Hsu A. Yang C. W. Lan 《Progress in Photovoltaics: Research and Applications》2015,23(3):340-351
The low cost and high quality of multicrystalline silicon (mc‐Si) based on directional solidification has become the main stream in photovoltaic (PV) industry. The mc‐Si quality affects directly the conversion efficiency of solar cells, and thus, it is crucial to the cost of PV electricity. With the breakthrough of crystal growth technology, the so‐called high‐performance mc‐Si has increased about 1% in solar cell efficiency from 16.6% in 2011 to 17.6% in 2012 based on the whole ingot performance. In this paper, we report our development of this high‐performance mc‐Si. The key ideas behind this technology for defect control are discussed. With the high‐performance mc‐Si, we have achieved an average efficiency of near 17.8% and an open‐circuit voltage (Voc) of 633 mV in production. The distribution of cell efficiency was rather narrow, and low‐efficiency cells (<17%) were also very few. The power of the 60‐cell module using the high‐efficiency cells could reach 261 W as well. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
104.
Yu Wang Lan Chen Qijing Wang Huabin Sun Xizhang Wang Zheng Hu Yun Li Yi Shi 《Organic Electronics》2014,15(10):2234-2239
To deposit organic semiconducting crystals from solution, we propose the use of a rollerball pen as a simple and promising tool. These organic crystal grains of dioctylbenzothienobenzothiophene measured several hundred micrometers. The fabricated OFETs exhibited good device performance with a field-effect mobility (μFET) of 0.7 cm2/Vs and an on-off ratio of more than 107. Simulation results reveal that the flow behavior of solution from the pen refill tube to the substrate intrinsically enhances the formation of large organic crystals. 相似文献
105.
欧姆接触锌电极的研制 总被引:4,自引:1,他引:3
对贱金属锌浆料进行了实验研究。材料配方的选择和工艺的优化是实验的关键。研制出的锌浆料可在大气中烧结在PTCR等半导瓷上构成电极。该贱金属锌电极能牢固地附着于陶瓷体上并具有优良的欧姆接触性能。 相似文献
106.
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108.
Yoshinobu Murakami Shinichi Mitsumoto Masumi Fukuma Naohiro Hozumi Masayuki Nagao 《Electrical Engineering in Japan》2002,138(3):19-25
This paper deals with the influence of interface between polyethylene and semiconducting electrode on the space charge formation and electrical breakdown. Low‐density polyethylene (LDPE) films attached with different semiconducting electrodes were subjected to the DC breakdown test, and corresponding space charge distribution was measured. A heat treatment to LDPE itself did not bring about a significant change in space charge profile; however, when a semiconducting electrode was hot‐pressed, the impurities would migrate into LDPE at high temperature, leading to the change in space charge profile. Furthermore, it was suggested from the comparison between the results with degassed and as‐received semiconducting electrodes that some carriers relating to impurities in the electrode would move into LDPE under the voltage. In addition, it was shown that the breakdown is not determined by the field at the cathode which can supply sufficient electrons, but by the maximum field across the specimen, suggesting that an increase in conduction current due to the generation and/or injection, rather than the electronic avalanche process, leads to the breakdown. © 2001 Scripta Technica, Electr Eng Jpn, 138(3): 19–25, 2002 相似文献
109.
A general overview of the optoelectronic properties of π‐conjugated polymers is presented. Two types of polymer are discerned: interchangeable structures of the same energy (degenerate), such as polyacetylene; and non‐degenerate polymers, such as poly(para‐phenylene). The band structures of degenerate and non‐degenerate polymers are related to their conductivities in doped and non‐doped states. In both cases, disorder and impurities play an important role in conductivity. Polarons, bipolarons and excitons are detailed with respect to doping and charge transfers. Given the fibrillic nature of these materials, the variable range hopping (VRH) law for semiconducting polymers is modified to account for metallic behaviours. Optoelectronic properties—electroluminescence and photovoltaic activity—are explained in terms of HOMO and LUMO bands, polaron‐exciton and charge movement over one or more molecules. The properties of H‐ or J‐type aggregates and their effects on transitions are related to target applications. Device structures of polymer light‐emitting diodes are explicitly linked to optimising polaron recombinations and overall quantum efficiencies. The particularly promising use of π‐conjugated polymers in photovoltaic devices is discussed. Copyright © 2004 Society of Chemical Industry 相似文献
110.
Highly Flexible Organic Nanofiber Phototransistors Fabricated on a Textile Composite for Wearable Photosensors
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Moo Yeol Lee Jayeon Hong Eun Kwang Lee Hojeong Yu Hyoeun Kim Jea Uk Lee Wonoh Lee Joon Hak Oh 《Advanced functional materials》2016,26(9):1445-1453
Highly flexible organic nanofiber phototransistors are fabricated on a highly flexible poly(ethylene terephthalate) (PET) textile/poly(dimethylsiloxane) (PDMS) composite substrate. Organic nanofibers are obtained by electrospinning, using a mixture of poly(3,3″′‐didodecylquarterthiophene) (PQT‐12) and poly(ethylene oxide) (PEO) as the semiconducting polymer and processing aid, respectively. PDMS is used as both a buffer layer for flattening the PET textile and a dielectric layer in the bottom‐gate bottom‐contact device configuration. PQT‐12:PEO nanofibers can be well‐aligned on the textile composite substrate by electrospinning onto a rotating drum collector. The nanofiber phototransistors fabricated on the PET/PDMS textile composite substrate show highly stable device performance (on‐current retention up to 82.3 (±6.7)%) under extreme bending conditions, with a bending radius down to 0.75 mm and repeated tests over 1000 cycles, while those prepared on film‐type PET and PDMS‐only substrates exhibit much poorer performances. The photoresponsive behaviors of PQT‐12:PEO nanofiber phototransistors have been investigated under light irradiation with different wavelengths. The maximum photoresponsivity, photocurrent/dark‐current ratio, and external quantum efficiency under blue light illumination were 930 mA W?1, 2.76, and 246%, respectively. Furthermore, highly flexible 10 × 10 photosensor arrays have been fabricated which are able to detect incident photonic signals with high resolution. The flexible photosensors described herein have high potential for applications as wearable photosensors. 相似文献