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Nano Research 2016年第7期9卷 1994-2006页

作者： Xu Chen Lucheng Peng Keke Huang Zhan Shi Renguo Xie Wensheng Yang College of Chemistry Jilin University Changchun 130012 China State Key Laboratory of Inorganic synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 China

Metal-halide perovskites are novel optoelectronic materials that are considered good candidates for solar harvesting and light emitting applications. In this study, we develop a reproducible and low-cost approach for synthesizing high- quality cesium lead halide perovskite （CsPbX3, X = CI, Br, and I or C1/Br and I/Br） nanocrystals （NCs） by direct heating of precursors in octadecene in air. Experimental results show that the particle size and composition of as-prepared CsPbX3 nanocrystals can be successfully tuned by a simple variation of reaction temperature. The emission peak positions of the as-prepared nanocrystals can be conveniently tuned from the UV to the NIR （360-700 nm） region, and the quantum yield of the as-obtained samples （green and red emissions） can reach up to 87%. The structures and chemical compositions of the as-obtained NCs were characterized by transmission electron microscopy, X-ray diffraction, and elemental analysis. This proposed synthetic route can yield large amounts of high-quality NCs with a one-batch reaction, usually on the gram scale, and could pave the way for further applications of perovskite-based light-emitting and photovoltaic solar cells.

关键词： metal-halide perovskites gram-scale synthesis controllable size andcomposition optoelectronic materials

Ultrasonication-assisted and gram-scale synthesis of Co-LDH nanosheet aggregates for oxygen evolution reaction

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Nano Research 2020年第1期13卷 79-85页

作者： Tian-Jiao Wang Xiaoyang Liu Ying Li Fumin Li Ziwei Deng Yu Chen Key Laboratory of Applied Surface and Colloid Chemistry(Ministry of Education) Key Laboratory of Macromolecular Science of Shaanxi ProvinceShaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringShaanxi Normal UniversityXi’an710062China School of Chemistry and Chemical Engineering Shaanxi Normal UniversityXi’an710062China

Electrochemical water splitting(EWS)is a highly clean and efficient method for high-purity hydrogen ***,EWS suffers from the sluggish and complex oxygen evolution reaction(OER)kinetics at *** present,the efficient,stable,and low-cost non-precious metal based OER electrocatalyst is still a great and long-term challenge for the future industrial application of EWS ***,we develop a simple and fast approach for gram-scale synthesis of flower-like cobalt-based layered double hydroxides nanosheet aggregates by ultrasonic synthesis,which show outstanding electrocatalytic performance for the oxygen evolution reaction in alkaline media,such as preeminent stability,small overpotential of 300 mV at 10 mA·cm^−2 and small Tafel slope of 110 mV·dec^−1.

关键词： electrochemical water splitting oxygen evolution reaction gram-scale synthesis layered double hydroxides nanosheet aggregates

High-metallic-phase-concentration MO1-xWxS2 nanosheets with expanded interlayers as efficient electrocatalysts

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Nano Research 2018年第3期11卷 1687-1698页

作者： Qun He Yangyang Wan Hongliang Jiang Chuanqiang Wu Zhongti Sun Shuangming Chen Yu Zhou Haiping Chen Daobin Liu Yasir A. Haleem Binghui Ge Xiaojun Wu Li Song National Synchrotron Radiation Laboratory CAS Center for Excellence in Nanoscience University of Science and Technology of China Hefei 230029 China CAS Key Lab of Materials for Energy Conversion CAS Center for Excellence in Nanoscience Hefei National Laboratory for Physical Science at the Microscale Synergetic Innovation of Quantum Information & Quantum Technology University of Science and Technology of China Hefei 230026 China Beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100190 China

In most cases, layered transition metal dichalcogenides （LTMDs）, containing metallic phases, show electrochemical behavior different from their semiconductor counterparts. Typically, two-dimensional layered metallic 1T-MoS2 demonstrates better electrocatalytic performance for water splitting compared to its 2H counterpart. However, the characteristics of low metallic phase concentration and poor stability limit its applications in some cases. Herein, we demonstrate a simple and efficient bottom-up wet-chemistry strategy for the large-scale synthesis of nanoscopic ultrathin Mo1-xWxS2 nanosheets with enlarged interlayer spacing and high metallic phase concentration. Our characterizations, including X-ray absorption fine structure spectroscopy （XAFS）, high-angle annular dark-field- scanning transmission electron microscopy （HAADF-STEM）, and X-ray photoelectron spectroscopy （XPS） revealed that the metallic ultrathin ternary Mo1-xWxS2 nanosheets exhibited distorted metal-metal bonds and a tunable metallic phase concentration. As a proof of concept, this optimized catalyst, with the highest metallic phase concentration （greater than 90%）, achieved a low overpotential of about -155 mV at a current density of -10 ma/cm^2, a small Tafel slope of 67 mV/dec, and an increased turnover frequency （TOF） of 1.3 H2 per second at an overpotential of -300 mV （vs. reversible hydrogen electrode （RHE））, highlighting the importance of the metallic phase. More importantly, this study can lead to a facile solvothermal route to prepare stable and high-metallic- phase-concentration transition-metal-based two-dimensional materials for future applications.

关键词： wet-chemistr gram-scale synthesis interlayer intercalation metallic transition metaldichalcogenide electrocatalytic water splitting

Facile access to chiral 4-substituted chromanes through Rh-catalyzed asymmetric hydrogenation

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Chinese Chemical Letters 2020年第7期31卷 1859-1862页

作者： Lin Tao Qingyang Zhao Xumu Zhang Xiu-Qin Dong Key Laboratory of Biomedical Polymers Engineering Research Centre of Organosilicon Compounds&MaterialsMinistry of EducationCollege of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072China Department of Chemistry and Shenzhen Grubbs Institute Southern University of Science and TechnologyShenzhen 518055China School of Pharmaceutical Sciences(Shenzhen) Sun Yat-sen UniversityShenzhen 518107China

Rh/ZhaoPhos-catalyzed asymmetric hydroge nation of a series of(E)-2-(chro man-4-ylidene)acetates was successfully developed to prepare various chiral 4-substituted chromanes with high yields and excellent enantioselectivities(up to 99%yield,98%ee).Moreover,the gram-scale hydrogenation could be performed well in the presence of 0.02 mol%catalyst loading(TON=5000),the hydrogenation product was easily converted to access other important compounds,which demonstrated the synthetic utility of this asymmetric catalytic methodology.

关键词： Chiral 4-substituted chromanes Asymmetric hydrogenation Excellent enantioselectivity gram-scale synthesis Bisphosphine-thiourea ligand

Photoinduced Radical Relay Way Towardα-CF_(3)Ketones with Low-Cost Trifluoromethylation Reagents

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CCS Chemistry 2021年第6期3卷 1710-1717页

作者： Huamin Wang Wenyan Shi Yongli Li Mingming Yu Yuan Gao Aiwen Lei Institute for Advanced Studies(IAS) College of Chemistry and Molecular SciencesWuhan UniversityWuhan 430072

The utilization of economic and practical trifluoromethyl reagents to introduce trifluoromethyl(CF_(3))groups into organic molecules is an important research focus due to their role as vital structuralmotifs in the pharmaceutical and agricultural ***,we disclose a cost-efficient and practical approach of photoinduction of a radical relay process for the synthesis ofα-CF_(3)*** showed that trifluoromethylation reagents such as TES-OTf,Tf2O,TMS-OTf,TBS-OTf,H-OTf,and others,could be used successfully as inexpensive CF_(3)precursors under metal-free and redox-neutral *** potential application of this protocol was highlighted further by late-state modification of drug segments and gram-scale *** mechanistic studies revealed that this transformation might involve a radical process,and acetic acid(CH3COOH)not only promoted the formation of enol triflates,but also accelerated the in situ conversion from enol triflates toα-CF_(3)ketones.

关键词： radical photoinduced process low-cost trifluoromethylation reagents α-CF_(3)ketones gram-scale synthesis

[5+2]环加成:秋水仙碱的8步全合成（英文）

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[5+2]环加成:秋水仙碱的8步全合成（英文）