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971.
Hydrogenated Bismuth Molybdate Nanoframe for Efficient Sunlight‐Driven Nitrogen Fixation from Air 下载免费PDF全文
Yuchen Hao Prof. Xiaoli Dong Prof. Shangru Zhai Prof. Hongchao Ma Xiuying Wang Prof. Xiufang Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(52):18722-18728
Sunlight‐driven dinitrogen fixation can lead to a novel concept for the production of ammonia under mild conditions. However, the efficient artificial photosynthesis of ammonia from ordinary air (instead of high pure N2) has never been implemented. Here, we report for the first time the intrinsic catalytic activity of Bi2MoO6 catalyst for direct ammonia synthesis under light irradiation. The edge‐exposed coordinatively unsaturated Mo atoms in an Mo?O coordination polyhedron can act as activation centers to achieve the chemisorption, activation, and photoreduction of dinitrogen efficiently. Using that insight as a starting point, through rational structure and defect engineering, the optimized Bi2MoO6 sunlight‐driven nitrogen fixation system, which simultaneously possesses robust nitrogen activation ability, excellent light‐harvesting performance, and efficient charge transmission was successfully constructed. As a surprising achievement, this photocatalytic system demonstrated for the first time ultra‐efficient (1.3 mmol g?1 h?1) and stable sunlight‐driven nitrogen fixation from air in the absence of any organic scavengers. 相似文献
972.
973.
Li Zhao Jiaguo Yu Jiajie Fan Pengcheng Zhai Shiming Wang 《Electrochemistry communications》2009,11(10):2052-2055
Dye-sensitized solar cells (DSSCs) are fabricated based on ordered titanate nanotube (TNT) films obtained by electrophoretic deposition (EPD) method. Calcination temperatures show a great influence on the performance of TNT solar cells. At 300 °C, the cells exhibit very low photo-electric conversion efficiency. At 400 °C, the efficiency obviously increases. At 600 °C, the cells show the highest efficiency, which is higher than the efficiency of the cells made from commercial-grade Degussa P25 TiO2 nanoparticles (P25). 相似文献
974.
Lixue Zhang Liang Wang Shaojun Guo Junfeng Zhai Shaojun Dong Erkang Wang 《Electrochemistry communications》2009,11(2):258-261
Monodisperse, submicrometer-scale platinum (Pt) colloidal spheres were prepared through a simple direct chemical reduction of p-phenylenediamine (PPD)-chloroplatinic acid (H2PtCl6) coordination polymer colloids. It was found that the prepared Pt colloids had the similar size and morphology with their coordination polymer precursors, and the prepared Pt colloids with rough surfaces were three-dimensional (3D) structured assemblies of high-density small Pt nanoparticles. The electrochemical experiments confirmed that the prepared Pt colloids possessed a high electrocatalytic activity towards mainly four-electron reduction of dioxygen to water, making the prepared Pt colloids potential candidates for the efficient cathode material in fuel cells. 相似文献
975.
Zhangquan Yao Ruirui Yue Fengxing Jiang Chunyang Zhai Fangfang Ren Yukou Du 《Journal of Solid State Electrochemistry》2013,17(9):2511-2519
A simple electrochemical approach is developed to prepare reduced graphene oxide (RGO)-wrapped carbon fiber (CF) as a novel support for Pt–Au nanocatalysts. The obtained composite electrodes have been characterized by scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (EDX), thermal gravimetric analysis (TGA), and electrochemical methods. SEM images reveal that the Pt–Au nanoparticles deposited on RGO-wrapped CF (RGO/CF) electrode display smaller particle size and more uniform dispersion than those on the bare CF electrode. Cyclic voltammetry, linear sweep voltammetry, chronoamperometry, chronopotentiometry, Tafel plots, and electrochemical impedance spectroscopy (EIS) analyses demonstrate that the introduced RGO on CF electrode surface is beneficial to the dispersion of Pt–Au nanoparticles, as a consequence, to the enhancement of the electrocatalytic activity and the antipoisoning ability of Pt–Au towards formic acid electrooxidation. 相似文献
976.
Jiaojiao Zhai Chunhui Gu Jianan Jiang Shunli Zhang Daohua Liao Lei Wang Dunru Zhu Yafei Ji 《中国化学》2013,31(12):1526-1538
A one-pot approach to ethyl 1,4,5-triaryl-lH-pyrazole-3-carboxylates has been developed in moderate to high yields. The tert-BuOLi-mediated Claisen condensation of 1,2-diarylethanones and ethyl oxalyl chloride efficiently provided the enolized lithium salts of ethyl 2,4-dioxo-3,4-diarylbutanoates, which in situ reacted with arylhydrazine hydrochlorides via a hydrochloric acid-promoted Knorr reaction to produce the exquisite triarylpyrazole-3- carboxylates. The procedure promises a convenient access to this highly crowded framework for drug discovery. 相似文献
977.
In this work, an ultrasensitive platform for the detection of cadmium (Cd2+) combining the nafion–graphene nanocomposite film with differential pulse anodic stripping voltammetry (DPASV) analysis was presented. It is found that this sensing platform exhibits enhanced response to the determination of the Cd2+ and has been used to determine the Cd2+ in real sample with good recovery. 相似文献
978.
Journal of Visualization - Aerodynamic flow around an 1/5 scale cyclist model was studied experimentally and numerically. First, measurements of drag force were performed for the model in a... 相似文献
979.
980.
催化燃烧用金属整体催化反应器的制备及性能 总被引:2,自引:0,他引:2
采用浸涂方法制备了甲烷催化燃烧用金属.催化剂整体化反应器。该反应器以铁铬合金为金属载体,六铝酸盐为催化剂。讨论了制备过程中金属载体预处理、Al2O3中间层、分散剂种类等因素对催化剂附着稳定性的影响。结果表明:铁铬合金在1100℃处理5h有助于形成稳定的保护层;Al2O3中间层的存在阻碍了六铝酸盐的浸涂;六铝酸盐直接浸涂在金属载体上并在一定温度焙烧可形成附着性很好的催化剂层,使之用于催化燃烧反应获得了良好效果。 相似文献