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1.
Jian-Kun Sun Linlin Zhang Liang Yue Tang Tang Wen-Jie Jiang Yun Zhang Zhenxiao Pan Xinhua Zhong Jin-Song Hu Li-Jun Wan 《中国科学:化学(英文版)》2018,61(10):1338-1344
Developing efficient counter electrodes (CEs) and quantum dots made of earth-abundant and non-toxic elements is essential but still challenging for quantum dot-sensitized solar cells (QDSSCs). Here, we report a facile strategy to prepare self-supported and robust CoS2 and NiS nanocrystals-assembled nanosheets directly grown on carbon paper (MSx NS@CP) as efficient counter electrodes for QDSSCs. Such CEs integrate the merits of fast electron transfer from interconnected conductive scaffold, efficient mass transfer from hierarchically vertical nanosheet on 3D open substrate, as well as abundant highly active catalytic sites from metal sulphide nanocrystal units. As a result, QDDSCs based on such CoS2 NS@CP and NiS NS@CP CEs achieve a PCE of 8.88% and 7.53%, respectively. The detailed analyses suggest that CoS2 NS@CP has the highest catalytic activity and shows the lowest charger transfer resistance, leading to the highest PCE. These findings may inspire the design and exploration of other self-supported efficient CEs by integrating highly active catalysts onto 3D conductive networks for efficient QDSSCs. 相似文献
2.
Dr. Weixin Zou Lixia Xu Yu Pu Haojie Cai Xiaoqian Wei Yidan Luo Dr. Lulu Li Prof. Dr. Bin Gao Prof. Dr. Haiqin Wan Prof. Dr. Lin Dong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(19):5058-5064
Bimetallic AgPd nanoparticles have been synthesized before, but the interfacial electronic effects of AgPd on the photocatalytic performance have been investigated less. In this work, the results of hydrogen evolution suggest that the bimetallic AgPd/g-C3N4 sample has superior activity to Ag/g-C3N4 and Pd/g-C3N4 photocatalysts. The UV/Vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, CO adsorption diffuse reflectance FTIR spectroscopy, and FTIR results demonstrate that in the AgPd/g-C3N4, the surface electronic structures of Pd and Ag are changed, which is beneficial for faster photogenerated electron transfer and greater H2O molecule adsorption. In situ ESR spectra suggest that, under visible light irradiation, there is more H2O dissociation to radical species on the AgPd/g-C3N4 photocatalyst. Furthermore, DFT calculations confirm the interfacial electronic effects of AgPd/g-C3N4, that is, Pdδ−⋅⋅⋅Agδ+, and the activation energy of H2O molecule dissociation on AgPd/g-C3N4 is the lowest, which is the main contributor to the enhanced photocatalytic H2 evolution. 相似文献
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4.
Chang Mingning Wang He Zheng Yonglei Li Ningning Chen Siheng Wan Yong Yuan Feng Shao Weiquan Xu Sheng 《Journal of Solid State Electrochemistry》2019,23(2):607-613
Journal of Solid State Electrochemistry - Li1.2Ni1/3Co1/3Mn1/3O2 was synthesized as a cathode material for lithium-ion batteries and coated with various amounts of CoAl2O4 (0–5 wt%)... 相似文献
5.
Zhu Xiaoyang Wang Jing Chai Lulu Tang Guangshi Wan Kangni Pan Junqing 《Journal of Solid State Electrochemistry》2022,26(5):1163-1173
Journal of Solid State Electrochemistry - In this work, nanorods like bimetallic Zn/Mn metal–organic-frameworks (MOFs) are proposed as the precursor for preparing MnxOy/porous carbon... 相似文献
6.
2017年,李昭祥等提出了一种偏牛顿-校正法(Partial Newton-Correction Method,简记为PNC方法),并利用它成功地计算出了三类非线性偏微分方程的多重不稳定解.本文在PNC方法的基础上,提出并发展了一种改进的PNC方法.首先,利用Nehari流形$\mathcal{N}$与零平凡解的可分离性,建立并证明了$\mathcal{N}$的某特殊子流形$\mathcal{M}$上的全局分离定理及其推广(即局部分离定理).全局分离定理只跟非线性偏微分算子或相应的非线性泛函本身有关,而与具体的计算方法无关.对一些典型的非线性偏微分方程多解问题(比如,Henon方程问题),该全局分离定理的分离条件,经验证是成立的.另一个方面,通过修改或补充原辅助变换的定义,去掉了原辅助变换的奇异性;接着建立并证明了某些非线性偏微分方程问题的新未知解与该非线性偏微分算子零核空间的密切关系;在证明中,去掉了在原奇异变换下所需的标准收敛(standard convergence)假设.最后,计算实例与数值结果验证了改进的PNC方法的可行性和有效性;同时表明子流形$\mathcal{M}$与已知解的可分离性是PNC方法和本文新方法能成功找到多解的关键. 相似文献
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8.
Dr. Wan‐Ling Liu Ni‐Shin Yang Ya‐Ting Chen Stephen Lirio Cheng‐You Wu Prof. Chia‐Her Lin Prof. Hsi‐Ya Huang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):115-119
A green and sustainable strategy synthesizes clinical medicine warfarin anticoagulant by using lipase‐supported metal–organic framework (MOF) bioreactors (see scheme). These findings may be beneficial for future studies in the industrial production of chemical, pharmaceutical, and agrochemical precursors. 相似文献
9.
Fangzhong Hu Xinxin Cheng Zixia Niu Xiaobing Yang Dan Li Lei Wan Junxiao Li Bin Liu Xiaomao Zou Huazheng Yang Bin Li 《Journal of heterocyclic chemistry》2015,52(3):793-801
A series of 3‐phenyl benzo[d][1,2,3]triazin‐4(3H)‐one derivatives were synthesized through the condensation of phenol E and alkyl (alkenyl, alkynyl) chlorides (bromides, iodide) or alkyl chloroacetates or N‐alkyl chloroacetamides using K2CO3 as the acid acceptor in N,N‐dimethylformamide. Phenol E was prepared from starting material, 5‐amino‐2‐chloro‐4‐fluorophenyl ethyl carbonate, in four steps involving in amidation, reduction, diazotization, and deprotecting‐group reaction. The herbicidal activities of the title compounds were tested against two dicotyledonous plants and two monocotyledonous plants, in which some of them exhibited high herbicidal activities against two dicotyledonous plants in preemergence and postemergence treatments. Moreover, when the dosage was decreased to 180 and 90 g/ha, compounds F1 , F8 , and F9 showed highly selective inhibitory activities against amaranth pigweed, alfalfa, asteraceae, field sowthistle, morning glory, purslane, and velvetleaf in postemergence treatment but had no herbicidal efficacy on rape except F1 , suggesting that it be possible to find a kind of herbicides to inhibit dicotyledonous weeds in the field of dicotyledonous crops with the same genus as aforementioned weeds. 相似文献
10.