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71.
Summary The photoconductivity of the magnetic semiconductor compound Cd1−x
Mn
x
Se has been studied at 300 K and at 77K for the first time for several Bridgman-grown single crystals. With this technique
it was possible to detect the Mn 3d level. Experimental data found in this investigation reveal that the Mn 3d level is pinned at 1.9 eV below the bottom of the conduction band,i.e. it is independent of temperature and insensitive to the amount of manganese.
Paper presented at the ?V International Conference on Ternary and Multinary Compounds?, held in Cagliari, September 14–16,
1982. 相似文献
72.
Summary The prominent photoelectric parameters of the semiconducting solid solutions Cu
x
Ag1−x
Cd2InTe4 are reported. From the spectral dependence of photoconductivity at room temperature and at 77 K the energy gaps and their
thermal coefficients are obtained. The detectivityD
*, the photocurrent gainG and the carrier lifetime are measured and the carrier mobility is deduced. In order to improve theD
* characteristics, the analysis of its parameters is also performed.
Paper presented at the ?V International Conference on Ternary and Multinary Compounds?, held in Cagliari, September 14–16,
1982. 相似文献
73.
Serge Beaupr Michel Belletête Gilles Durocher Mario Leclerc 《Macromolecular theory and simulations》2011,20(1):13-18
A reliable model that can be used to estimate the electronic properties (i.e., the HOMO, LUMO, and band gap energies) of conjugated polymers would be a great tool for applications in organic electronics such as light‐emitting diodes, field‐effect transistors, and photovoltaic cells. Recently, poly(2,7‐carbazole) derivatives have shown promising results when used as an active donor layer in bulk heterojunction photovoltaic cells with power conversion efficiency exceeding 7%. By using a simple correlation between density functional theory (DFT) theoretical calculations performed on six model compounds (using the repeating unit) and experimental data from the six corresponding polymers, an accurate estimation of the HOMO energy level, the LUMO energy levels, and the band gap of several poly(2,7‐carbazole) derivatives was obtained. According to the theoretical data obtained for more than one hundred repeating units, fourteen new copolymers that can be used as p‐type materials in bulk heterojunction solar cells were selected and synthesized. Experimental data obtained from these materials were then used to refine the correlation between DFT and experimental data of poly(2,7‐carbazole) derivatives.
74.
Auf der Basis von 85Kr wurde ein Prüfstand für die routinemäßge Dichtigkeitsprüfung von Halbleiterbauelementen entwickelt und gebaut. Die Anlage arbeitet mit einer Aktivkohlepumpe und ist für einen Maximaldruck ion 13 kp/cm2 und eine Maximalaktivität von 40Ci85Kr ausgelegt. Es werden einige theoretische Angaben zur Methode gemacht und der Auf ban sowie die Funktionsweise des Prüfstandes beschrieben. Die erhaltenen Ergebnisse werden mit denen anderer Methoden verglichen. 相似文献
75.
Effect of branched alkyl side chains on the performance of thin‐film transistors and photovoltaic cells fabricated with isoindigo‐based conjugated polymers 下载免费PDF全文
Gi Eun Park Jicheol Shin Dae Hee Lee Min Ju Cho Dong Hoon Choi 《Journal of polymer science. Part A, Polymer chemistry》2015,53(10):1226-1234
New isoindigo and di(thienyl)ethylene‐containing π‐extended conjugated polymers with different branched side chains were synthesized to investigate their physical properties and device performance in thin‐film transistors and photovoltaic cells. 11‐Butyltricosane (S3) and 11‐heptyltricosane (S6) groups were used as side‐chain moieties tethered to isoindigo units. The linking groups between the polymer backbone and bifurcation point in the branched side chain differ in the two polymers (i.e., PIDTE‐S3 and PIDTE‐S6 ). The polymers bearing S6 side chains showed much better charge transport behavior than those with S3 side chains. Thermally annealed PIDTE‐S6 film exhibited an outstanding hole mobility of 4.07 cm2 V?1 s?1 under ambient conditions. Furthermore, bulk heterojunction organic photovoltaic cells made from a blend film of PIDTE‐S3 and (6,6)‐phenyl C61‐butyric acid methyl ester demonstrated promising device performance with a power conversion efficiency in the range of 4.9–5.0%. © 2015 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 2015 , 53, 1226–1234 相似文献
76.
A Photoferroelectric Perovskite‐Type Organometallic Halide with Exceptional Anisotropy of Bulk Photovoltaic Effects 下载免费PDF全文
Dr. Zhihua Sun Dr. Xitao Liu Tariq Khan Chengmin Ji Muhammad Adnan Asghar Dr. Sangen Zhao Dr. Lina Li Prof. Maochun Hong Prof. Junhua Luo 《Angewandte Chemie (International ed. in English)》2016,55(22):6545-6550
Perovskite‐type ferroelectrics composed of organometallic halides are emerging as a promising alternative to conventional photovoltaic devices because of their unique photovoltaic effects (PVEs). A new layered perovskite‐type photoferroelectric, bis(cyclohexylaminium) tetrabromo lead ( 1 ), is presented. The material exhibits an exceptional anisotropy of bulk PVEs. Upon photoexcitation, superior photovoltaic behaviors are created along its inorganic layers, which are composed of corner‐sharing PbBr6 octahedra. Semiconducting activity with remarkable photoconductivity is achieved in the vertical direction, showing sizeable on/off current ratios (>104), which compete with the most active photovoltaic material CH3NH3PbI3. In 1 the temperature‐dependence of photovoltage coincides fairly well with that of polarization, confirming the dominant role of ferroelectricity in such highly anisotropic PVEs. This finding sheds light on bulk PVEs in ferroelectric materials, and promotes their application in optoelectronic devices. 相似文献
77.
Inside Back Cover: Monodisperse Dual‐Functional Upconversion Nanoparticles Enabled Near‐Infrared Organolead Halide Perovskite Solar Cells (Angew. Chem. Int. Ed. 13/2016) 下载免费PDF全文
78.
Eunhee Lim 《Molecular Crystals and Liquid Crystals》2016,635(1):94-101
ABSTRACTAn acceptor-donor-acceptor (A–D–A)-type small molecule, BDT-IN, having a benzo[1,2-b:4,5-b']dithiophene (BDT) unit as its electron-donating core (D) and an 1,3-indanedione (IN) unit as its electron-withdrawing end group (A), was synthesized by Knoevenagel condensation. The BDT-IN film showed broader UV absorption with a greater red shift (λmax = 622 nm) than that of the BDT-IN solution (λmax = 570 nm). The organic photovoltaic cells were fabricated with an ITO/PEDOT:PSS/poly(3-hexylthiophene): BDT-IN/LiF/Al configuration, and showed a power conversion efficiency of 0.23%. 相似文献
79.
Photovoltaic phenomenon in tetracene and pentacene layers evaporated under the same conditions onto a glass substrate and provided with the same couple of electrodes is investigated. Comparison of the results obtained for both organic materials makes it possible to conclude that in spite of differences in mechanisms of charge carrier generation, the values of photovoltaic parameters are very similar. 相似文献
80.