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141.
薄膜太阳电池的研究进展 总被引：25，自引：0，他引：25
介绍了薄膜太阳电池在光伏技术中的位置,详细叙述了非晶硅,铜铟锡,碲化镉等主要薄膜太阳电池的基本结构,制造方法,研究进展和现状,指出了存在的关键问题和解决的途径,并介绍了薄膜太阳电池的发展趋势和应用前景。 相似文献
142.
Yuexin Sun;Guangzhou Geng;Yanchun Wang;Yuebian Zhang;Zhancheng Li;Wenwei Liu;Hua Cheng;Shuqi Chen; 《Laser u0026amp; Photonics Reviews》2024,18(6):2300866
The superior capability of wavefront manipulation makes metasurfaces a promising platform for implementing high-density information storage and multifold optical encryption. Although some metasurfaces have realized information encryption, it is still challenging to implement polarization-encrypted grayscale images in both linear and nonlinear channels. Here, a novel approach to realize multichannel linear and nonlinear information encryptions is proposed based on nonlinear Malus metasurfaces composed of single-sized meta-atoms, in which the polarization states of the linear and nonlinear signals can be decoupled. As a proof of concept, two distinct grayscale images with different polarizations have been encrypted in the fundamental and second harmonic wave channels simultaneously. Besides, by further introducing the nonlinear Pancharatnam-Berry phase, a tri-channel polarization encrypted metasurface with a multi-level grayscale image in the near field and two holographic images in the far field has been experimentally demonstrated at the second harmonic frequency. This work provides more degrees of freedom for multichannel information storage and opens an avenue for optical information encryption in both linear and nonlinear regimes. 相似文献
143.
Prof. Dr. Jilai Li Dr. Caiyun Geng Dr. Thomas Weiske Prof. Dr. Mingfei Zhou Prof. Dr. Jun Li Prof. Dr. Helmut Schwarz 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(39):17414-17418
Extensive high-level quantum-chemical calculations reveal that the rod-shaped molecule BeOBeC, which was recently generated in matrix experiments, exists in two nearly isoenergetic states, the 5Σ quintet (5 6 ) and the 3Σ triplet (3 6 ). Their IR features are hardly distinguishable at finite temperature. The major difference concerns the mode of spin coupling between the terminal beryllium and carbon atoms. Further, the ground-state potential-energy surface of the [2Be,C,O] system at 4 K is presented and differences between the photochemical and thermal behaviors are highlighted. Finally, a previously not considered, so far unknown C2v-symmetric rhombus-like four-membered ring 3[Be(O)(C)Be] (3 5 ) is predicted to represent the global minimum on the potential-energy surface. 相似文献
144.
Hongyang Su Lanlan Chen Yizhen Chen Prof. Rui Si Yuting Wu Xiaonan Wu Dr. Zhigang Geng Prof. Wenhua Zhang Prof. Jie Zeng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(46):20591-20596
Efforts have been devoted to achieving a highly efficient artificial synthesis of ammonia (NH3). Reported herein is a novel Fe-MoS2 catalyst with Fe atomically dispersed onto MoS2 nanosheets, imitating natural nitrogenase, to boost N2 electroreduction into NH3 at room temperature. The Fe-MoS2 nanosheets exhibited a faradic efficiency of 18.8 % with a yield rate of 8.63 μg mgcat.−1 h−1 for NH3 at −0.3 V versus the reversible hydrogen electrode. The mechanism study revealed that the electroreduction of N2 was promoted and the competing hydrogen evolution reaction was suppressed by decorating the edge sites of S in MoS2 with the atomically dispersed Fe, resulting in high catalytic performance for the electroreduction of N2 into NH3. This work provides new ideas for the design of catalysts for N2 electroreduction and strengthens the understanding about N2 activation over Mo-based catalysts. 相似文献
145.
Tian Du Ruiheng Gao Dr. Yunfeng Deng Cheng Wang Qian Zhou Prof. Yanhou Geng 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(1):227-231
A series of 1,3-indandione-terminated π-conjugated quinoids were synthesized by alkoxide-mediated rearrangement reaction of the respective alkene precursors, followed by air oxidation. This new protocol allows access to quinoidal compounds with variable termini and cores. The resulting quinoids all show LUMO levels below −4.0 eV and molar extinction coefficients above 105 L mol−1 cm−1. The optoelectronic properties of these compounds can be regulated by tuning the central cores as well as the aryl termini ascribed to the delocalized frontier molecular orbitals over the entire molecular skeleton involving aryl termini. n-Channel organic thin-film transistors with electron mobility of up to 0.38 cm2 V−1 s−1 were fabricated, showing the potential of this new class of quinoids as organic semiconductors. 相似文献
146.
147.
Wenhao Geng Prof. Wei Chen Guihua Li Xiao Dong Yanfang Song Prof. Wei Wei Prof. Yuhan Sun 《ChemSusChem》2020,13(16):4035-4040
Metal−organic frameworks (MOFs), combining the advantages of heterogeneous and homogeneous components, have been explored as catalytic materials for the CO2 electroreduction reaction (CO2ERR). However, the unmatched metal nodes result in MOFs having lower faradaic efficiencies (FEs) and limited current densities in CO2ERR. Herein, we report a general strategy to promote activities of MOFs via node doping in CO2ERR. With ion exchange, an active tin node was doped into zeolitic imidazolate framework-8 (ZIF-8) to facilitate the reduction kinetics of CO2. The divalent Sn2+ node accelerates the formation of formic acid (HCOOH), resulting in the highest HCOOH FE of 74 % and total current density (Jtotal) of 27 mA/cm2 at −1.1 V (vs. reversible hydrogen electrode, RHE) over 0.6 wt% Sn-doped ZIF-8 with stable catalytic performance after seven reuse cycles, which is clearly better compared to the catalytic properties of pristine ZIF-8 (FEHCOOH=0 %, Jtotal=13 mA/cm2). This work opens an avenue for promoting the CO2ERR performance of MOFs by node doping. 相似文献
148.
Wen‐Chao Geng Dongmei Zhang Chu Gong Zhihao Li Kevin M. Barraza Jesse L. Beauchamp Dong‐Sheng Guo Xinxing Zhang 《Angewandte Chemie (International ed. in English)》2020,59(31):12684-12688
The oxidation of antioxidants by oxidizers imposes great challenges to both living organisms and the food industry. Here we show that the host–guest complexation of the carefully designed, positively charged, amphiphilic guanidinocalix[5]arene pentadodecyl ether (GC5A‐12C) and negatively charged oleic acid (OA), a well‐known cell membrane antioxidant, prevents the oxidation of the complex monolayers at the air–water interface from two potent oxidizers hydroxyl radicals (OH) and singlet delta oxygen (SDO). OH is generated from the gas phase and attacks from the top of the monolayer, while SDO is generated inside the monolayer and attacks amphiphiles from a lateral direction. Field‐induced droplet ionization mass spectrometry results have demonstrated that the host–guest complexation achieves steric shielding and prevents both types of oxidation as a result of the tight and “sleeved in” physical arrangement, rather than the chemical reactivity, of the complexes. 相似文献
149.
Zhiyuan Ma Jie Liu Jinbo Fei Ning He Dr. Panpan Wang Dr. Jiaqi Wang Zhe Chen Zhenyuan Ji Hua Wang Dr. Wei Ling Ningyuan Nie Mengmeng Hu Prof. Yan Huang 《ChemElectroChem》2020,7(19):3998-4002
Yarn batteries are extensively used in portable, flexible and wearable electronics due to their tiny volume, good flexibility and maximum compatibility with textiles. However, both the flammable organic electrolyte and the hydrogel electrolyte are not capable of solving safety issues. In this work, a poly(ionic liquid)(PIL)-based ionogel was synthesized as an electrolyte with both superior flame resistance and high ionic conductivity. The flexible Li4Ti5O12//LiFePO4 yarn battery based on the ionogel not only has the safety characteristic of incombustibility, but also guarantees stable electrochemical properties under cold and hot weather conditions. 相似文献
150.
Ship-radiated noise is one of the important signal types under the complex ocean background, which can well reflect physical properties of ships. As one of the valid measures to characterize the complexity of ship-radiated noise, permutation entropy (PE) has the advantages of high efficiency and simple calculation. However, PE has the problems of missing amplitude information and single scale. To address the two drawbacks, refined composite multi-scale reverse weighted PE (RCMRWPE), as a novel measurement technology of describing the signal complexity, is put forward based on refined composite multi-scale processing (RCMP) and reverse weighted PE (RWPE). RCMP is an improved method of coarse-graining, which not only solves the problem of single scale, but also improves the stability of traditional coarse-graining; RWPE has been proposed more recently, and has better inter-class separability and robustness performance to noise than PE, weighted PE (WPE), and reverse PE (RPE). Additionally, a feature extraction scheme of ship-radiated noise is proposed based on RCMRWPE, furthermore, RCMRWPE is combined with discriminant analysis classifier (DAC) to form a new classification method. After that, a large number of comparative experiments of feature extraction schemes and classification methods with two artificial random signals and six ship-radiated noise are carried out, which show that the proposed feature extraction scheme has better performance in distinguishing ability and stability than the other three similar feature extraction schemes based on multi-scale PE (MPE), multi-scale WPE (MWPE), and multi-scale RPE (MRPE), and the proposed classification method also has the highest recognition rate. 相似文献