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101.
Dr. Ying Wang Dr. Wenming Sun Xiaofei Ling Xiangkai Shi Dr. Lanlan Li Prof. Yida Deng Dr. Cuihua An Dr. Xiaopeng Han 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(18):4097-4103
The development of high-efficiency, low-cost, and earth-abundant electrocatalysts for overall water splitting remains a challenge. In this work, Ni-modified MoS2 hybrid catalysts are grown on carbon cloth (Ni-Mo-S@CC) through a one-step hydrothermal treatment. The optimized Ni-Mo-S@CC catalyst shows excellent hydrogen evolution reaction (HER) activity with a low overpotential of 168 mV at a current density of 10 mA cm−2 in 1.0 m KOH, which is lower than those of Ni-Mo-S@CC (1:1), Ni-Mo-S@CC (3:1), and pure MoS2. Significantly, the Ni-Mo-S@CC hybrid catalyst also displays outstanding oxygen evolution reaction (OER) activity with a low overpotential of 320 mV at a current density of 10 mA cm−2, and remarkable long-term stability for 30 h at a constant current density of 10 mA cm−2. Experimental results and theoretical analysis based on density functional theory demonstrate that the excellent electrocatalytic performance can be attributed mainly to the remarkable conductivity, abundant active sites, and synergistic effect of the Ni-doped MoS2. This work sheds light on a unique strategy for the design of high-performance and stable electrocatalysts for water-splitting electrolyzers. 相似文献
102.
Dr. Zongrui Wang Dr. Fei Yu Dr. Jian Xie Prof. Jianfeng Zhao Ye Zou Zepeng Wang Prof. Qichun Zhang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(16):3578-3585
Although cocrystallization has provided a promising platform to develop new organic optoelectronic materials, it is still a big challenge to purposely design and achieve specific optoelectronic properties. Herein, a series of mixed-stacking cocrystals (TMFA, TMCA, and TMTQ) were designed and synthesized, and the regulatory effects of the acceptors on the co-assembly behavior, charge-transfer nature, energy-level structures, and optoelectronic characteristics were systematically investigated. The results demonstrate that it is feasible to achieve effective charge-transport tuning and photoresponse switching by carefully regulating the intermolecular charge transfer and energy orbitals. The inherent mechanisms underlying the change in these optoelectronic behaviors were analyzed in depth and elucidated to provide clear guidelines for future development of new optoelectronic materials. In addition, due to the excellent photoresponsive characteristics of TMCA, TMCA-based phototransistors were investigated with varying light wavelength and optical power, and TMCA shows the best performance among all reported cocrystals under UV illumination. 相似文献
103.
Xiong Sun Dr. Wei Su Kaiying Shi Zhuoyi Xie Prof. Dr. Congqing Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(24):5354-5359
Rare-earth metal cations have been used rarely as Lewis-acidic components in the chemistry of frustrated Lewis pairs (FLPs). Herein, we report the first cerium/phosphorus system ( 2 ) employing a heptadentate N4P3 ligand, which exhibits triple FLP-type reactivity towards a series of organic substrates, including isocyanates, isothiocyanates, diazomethane, and azides on a single rare-earth Lewis acidic Ce center. This result shows that the Ce center and three P atoms in 2 could simultaneously activate three equivalents of small molecules under mild conditions. This study broadens the diversity of FLPs and demonstrates that rare earth based FLP exhibit unique properties compared with other FLP systems. 相似文献
104.
Ji Wang Nan Li Yuxia Xu Prof. Dr. Huan Pang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(29):6402-6422
Metal–organic framework (MOF) and covalent organic framework (COF) nanosheets are a new type of two-dimensional (2D) materials with unique design principles and various synthesis methods. They are considered ideal electrochemical devices due to the ultrathin thickness, easily tunable molecular structure, large porosity and other unique properties. There are two common methods to synthesize 2D MOF/COF nanosheets: bottom-up and top-down. The top-down strategy mainly includes ultrasonic assisted exfoliation, electrochemical exfoliation and mechanical exfoliation. Another strategy mainly includes interface synthesis, modulation synthesis, surfactant-assisted synthesis. In this Review, the development of ultrathin 2D nanosheets in the field of electrochemistry (supercapacitors, batteries, oxygen reduction, and hydrogen evolution) is introduced, and their unique dimensional advantages are highlighted. 相似文献
105.
Dr. Saud Asif Ahmed Qiao-Bo Liao Qi Shen Dr. Mirza Muhammad Faran Ashraf Baig Juan Zhou Cai-Feng Shi Dr. Pir Muhammad Dr. Sumaira Hanif Prof. Kai Xi Prof. Xing-Hua Xia Prof. Kang Wang 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(57):12996-13001
Layered/two-dimensional covalent organic frameworks (2D COF) are crystalline porous materials composed of light elements linked by strong covalent bonds. Interlayer force is one of the main factors directing the formation of a stacked layer structure, which plays a vital role in the stability, crystallinity, and porosity of layered COFs. The as-developed new way to modulate the interlayer force of imine-linked 2D TAPB-PDA-COF (TAPB = 1,3,5-tris(4-aminophenyl)benzene, PDA = terephthaldehyde) by only adjusting the pH of the solution. At alkaline and neutral pH, the pore size of the COF decreases from 34 Å due to the turbostratic effect. Under highly acidic conditions (pH 1), TAPB-PDA-COF shows a faster and stronger turbostratic effect, thus causing the 2D structure to exfoliate. This yields bulk quantities of an exfoliated few/single-layer 2D COF, which was well dispersed and displayed a clear Tyndall effect (TE). Furthermore, nanopipette-based electrochemical testing also confirms the slipping of layers with increase towards acidic pH. A model of pH-dependent layer slipping of TAPB-PDA-COF was proposed. This controllable pH-dependent change in the layer structure may open a new door for potential applications in controlled gas adsorption/desorption and drug loading/releasing. 相似文献
106.
Yichen Zhou Mingmin Jia Dr. Xiongfei Zhang Prof. Dr. Jianfeng Yao 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(35):7918-7922
Zeolite ZIF-8 has been etched with acid to form microporous ZIF-8-E crystals. These were then introduced into a polyethersulfone (PES) membrane matrix to enhance its CO2/N2 separation performance. Open through pores of size about 100 nm formed in the ZIF-8 crystals allow the ingrowth of polyethersulfone chains, ensuring a reduction in the number of nonselective voids, thereby achieving better interaction between ZIF-8-E and PES. As a result, the CO2/N2 separation performance of the ZIF-8-E/PES membrane increased significantly, showing a CO2 permeability of 15.7 Barrer and a CO2/N2 ideal selectivity of 6.5. 相似文献
107.
Ram Ambre Ting-Hsuan Wang Anmei Xian Yu-Shiuan Chen Yu-Fu Liang Prof. Titel Jurca Prof. Lili Zhao Prof. Tiow-Gan Ong 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(71):17021-17026
A simple Ni(cod)2 and carbene mediated strategy facilitates the efficient catalytic cross-coupling of methoxyarenes with a variety of organoboron reagents. Directing groups facilitate the activation of inert C−O bonds in under-utilized aryl methyl ethers enabling their adaptation for C−C cross-coupling reactions as less toxic surrogates to the ubiquitous haloarenes. The method reported enables C−C cross-coupling with readily available and economical arylboronic acid reagents, which is unprecedented, and compares well with other organoboron reagents with similarly high reactivity. Extension to directing group assisted chemo-selective C−O bond cleavage, and further application towards the synthesis of novel bifunctionalized biaryls is reported. Key to the success of this protocol is the use of directing groups proximal to the reaction center to facilitate the activation of the inert C−OMe bond. 相似文献
108.
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110.
Journal of Radioanalytical and Nuclear Chemistry - The stable isotope-labeled rosuvastatin was requested in order to fully understand the metabolic process of rosuvastatin. An effective synthesis... 相似文献