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31.
Electroluminescence explored internal behavior of carriers in InGaAsP single-junction solar cell 下载免费PDF全文
Xue-Fei Li 《中国物理 B》2023,32(1):17801-017801
The internal behaviors of carriers in InGaAsP single-junction solar cell are investigated by using electroluminescence (EL) measurements. Two emission peaks can be observed in current-dependent electroluminescence spectra at low temperatures, and carrier localization exists for both peaks under low excitation. The trends of power index α extracted from excitation-dependent EL spectra at different temperatures imply that there exists a competition between Shockley-Read-Hall recombination and Auger recombination. Auger recombination becomes dominant at high temperatures, which is probably responsible for the lower current density of InGaAsP solar cell. Besides, the anomalous "S-shape" tendency with the temperature of band-edge peak position can be attributed to potential fluctuation and carrier redistribution, demonstrating delocalization, transfer, and redistribution of carriers in the continuum band-edge. Furthermore, the strong reduction of activation energy at high excitations indicates that electrons and holes escaped independently, and the faster-escaping carriers are holes. 相似文献
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A new high spectral resolution crystal spectrometer is designed to measure very low emissive X-ray spectra of laser-produced plasma in 0.5-0.9 nm range. A large open aperture (30 ×20 (mm)) mica (002) spherically bent crystal with curvature radius R = 380 mm is used as dispersive and focusing element. The imaging plate is employed to obtain high spectral resolution with effective area of 30 × 80 (mm). The long designed path of the X-ray spectrometer beam is 980 mm from the source to the detector via the crystal. Experiment is carried out at a 20-J laser facility. X-ray spectra in an absolute intensity scale is obtained from Al laserproduced plasmas created by laser energy of 6.78 J. Samples of spectra obtained with spectral resolution of up to E/△E - 1500 are presented. The results clearly show that the device is good to diagnose laser high-density plasmas. 相似文献
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0.6-eV bandgap In0.69Ga0.31As thermophotovoltaic devices with compositionally undulating step-graded InAsyP1-y buffers 下载免费PDF全文
Single-junction,lattice-mismatched In0.69Ga0.31As thermophotovoltaic(TPV) devices each with a bandgap of 0.6 eV are grown on InP substrate by metal-organic chemical vapour deposition(MOCVD).Compositionally undulating stepgraded InAsyP1-y buffer layers with a lattice mismatch of ~1.2% are used to mitigate the effect of lattice mismatch between the device layers and the InP substrate.With an optimized buffer thickness,the In0.69Ga0.31As active layers grown on the buffer display a high crystal quality with no measurable tetragonal distortion.High-performance single-junction devices are demonstrated,with an open-circuit voltage of 0.215 V and a photovoltaic conversion efficiency of 6.9% at a short-circuit current density of 47.6 mA/cm2,which are measured under the standard solar simulator of air mass 1.5-global(AM 1.5 G). 相似文献
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全氟3,4-二甲基-4-乙基-2-己烯(1)和含硫亲核试剂如苄硫酚、烯丙硫酚及苯硫酚等的反应及反应产物的转化可得四类异构体2,3,4,5;在-30~-60℃于乙醚中反应,得到动力学控制的产物2a~c。2a,2b与KF在DMF中,室温反应可转化为热力学稳定的产物3a,3b。在100~120℃,2a~c异构化为4a~c。后者在DMF-KF中室温反应,重排成5a~c。在DMF-NEt_3中2a再和苄硫酚反应得到连二苄硫醚(6)和含氢的端基烯7a及二取代产物8a,在乙醚-三乙胺中反应得到3a和9a。2a和甲醇反应,可得少量3a和10a。2b和二乙胺反应复杂,仅得少量3b和不饱和酰胺11。 相似文献
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