检索结果-南通市图书馆

atomically dispersed Main Group Magnesium on Cadmium Sulfide as the Active Site for Promoting Photocatalytic Hydrogen Evolution Catalysis

在线全文

学校读者我要写书评

暂无评论

引用

Chinese Journal of Structural Chemistry 2022年第1期41卷 14-18页

作者： Ran Chen Juan Chen Huinan Che Gang Zhou Yanhui Ao Bin Liu Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes Ministry of EducationCollege of EnvironmentHohai UniversityNanjing 210098China School of Chemical and Biomedical Engineering Nanyang Technological UniversitySingapore 637459Singapore Division of Chemistry and Biological Chemistry School of Physical and Mathematical SciencesNanyang Technological University21 Nanyang LinkSingapore 637371Singapore

Photoabsorption charge separation/transfer and surface reaction are the three main factors influencing the efficiency of photocatalysis.Band structure engineering has been extensively applied to improve the light absorption of photocatalysts,however,most of the developed photocatalysts still suffer from low photocatalytic performance due to the limited active site(s)and fast recombination of photogenerated charge carriers.In this work,atomically dispersed main group magnesium(Mg)is introduced onto CdS monodispersed nanospheres,which greatly enhances the photocatalytic hydrogen evolution reaction.The photocatalytic hydrogen evolution reaction rate reaches 30.6 mmol·gcatalyst^(-1)·h^(-1),which is about 11.8 and 2.5 times that of pure CdS and Pt(2 wt.%)-CdS.The atomically dispersed Mg on CdS acts as an electron sink to trap photogenerated electrons,and at the same time,greatly reduces the Gibbs free energy of hydrogen evolution reaction(HER)and accelerates HER.

关键词： CdS hydrogen photocatalysis atomically dispersed main group metal

Oxygen‑Coordinated Single Mn Sites for Efficient Electrocatalytic Nitrate Reduction to Ammonia

在线全文

学校读者我要写书评

暂无评论

引用

Nano-Micro Letters 2024年第1期16卷 147-159页

作者： Shengbo Zhang Yuankang Zha Yixing Ye Ke Li Yue Lin Lirong Zheng Guozhong Wang Yunxia Zhang Huajie Yin Tongfei Shi Haimin Zhang Laboratory of Materials Physics Centre for Environmental and Energy NanomaterialsAnhui Key Laboratory of Nanomaterials and NanotechnologyCAS Center for Excellence in NanoscienceInstitute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031People’s Republic of China University of Science and Technology of China Hefei 230026People’s Republic of China Key Laboratory of Agricultural Sensors Ministry of AgricultureSchool of Information and ComputerAnhui Agricultural UniversityHefei 230026People’s Republic of China Hefei National Research Center for Physical Sciences at the Microscale University of Science and Technology of ChinaHefei 230026People’s Republic of China Beijing Synchrotron Radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences19B Yuquan RoadBeijing 100049People’s Republic of China

Electrocatalytic nitrate reduction reaction has attracted increasing attention due to its goal of low carbon emission and environmental protection.Here,we report an efficient NitRR catalyst composed of single Mn sites with atomically dispersed oxygen(O)coordination on bacterial cellulose-converted graphitic carbon(Mn-O-C).Evidence of the atomically dispersed Mn-(O-C_(2))_(4)moieties embedding in the exposed basal plane of carbon surface is confirmed by X-ray absorption spectroscopy.As a result,the as-synthesized Mn-O-C catalyst exhibits superior NitRR activity with an NH_(3)yield rate(RNH_(3))of 1476.9±62.6μg h^(−1)cm^(−2)at−0.7 V(vs.reversible hydrogen electrode,RHE)and a faradaic efficiency(FE)of 89.0±3.8%at−0.5 V(vs.RHE)under ambient conditions.Further,when evaluated with a practical flow cell,Mn-O-C shows a high RNH_(3)of 3706.7±552.0μg h^(−1)cm^(−2)at a current density of 100 mA cm−2,2.5 times of that in the H cell.The in situ FT-IR and Raman spectroscopic studies combined with theoretical calculations indicate that the Mn-(O-C_(2))_(4)sites not only effectively inhibit the competitive hydrogen evolution reaction,but also greatly promote the adsorption and activation of nitrate(NO_(3)^(−)),thus boosting both the FE and selectivity of NH_(3)over Mn-(O-C_(2))_(4)sites.

关键词： atomically dispersed Oxygen coordination Nitrate reduction reaction In situ spectroscopic studies Hydrogen evolution reaction

Engineering Fe‑N_(4)Electronic Structure with Adjacent Co‑N_(2)C_(2)and Co Nanoclusters on Carbon Nanotubes for Efficient Oxygen Electrocatalysis

在线全文

学校读者我要写书评

暂无评论

引用

纳微快报:英文版 2023年第12期15卷 283-297页

作者： Mingjie Wu Xiaohua Yang Xun Cui Ning Chen Lei Du Mohamed Cherif Fu‑Kuo Chiang Yuren Wen Amir Hassanpour Francois Vidal Sasha Omanovic Yingkui Yang Shuhui Sun Gaixia Zhang State Key Laboratory of New Textile Materials and Advanced Processing Technologies Wuhan Textile UniversityWuhan 430200People’s Republic of China Institut National de la Recherche Scientifique(INRS) Center Energie Materiaux TelecommunicationsVarennesQC J3X 1P7Canada Department of Chemical Engineering McGill University3610 University StreetMontrealQC H3A 0C5Canada Department of Electrical Engineering Ecole de Technologie Superieure(ETS)MontrealQC H3C 1K3Canada Canadian Light Source(CLS) 44 Innovation BoulevardSaskatoonSK S7N 2V3Canada National Institute of Low-Carbon-and-Clean-Energy Beijing 102211People’s Republic of China School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083People’s Republic of China

Regulating the local configuration of atomically dispersed transition-metal atom catalysts is the key to oxygen electrocatalysis performance enhancement.Unlike the previously reported singleatom or dual-atom configurations,we designed a new type of binary-atom catalyst,through engineering Fe-N_(4)electronic structure with adjacent Co-N_(2)C_(2)and nitrogen-coordinated Co nanoclusters,as oxygen electrocatalysts.The resultant optimized electronic structure of the Fe-N_(4)active center favors the binding capability of intermediates and enhances oxygen reduction reaction(ORR)activity in both alkaline and acid conditions.In addition,anchoring M-N-C atomic sites on highly graphitized carbon supports guarantees of efficient charge-and mass-transports,and escorts the high bifunctional catalytic activity of the entire catalyst.Further,through the combination of electrochemical studies and in-situ X-ray absorption spectroscopy analyses,the ORR degradation mechanisms under highly oxidative conditions during oxygen evolution reaction processes were revealed.This work developed a new binary-atom catalyst and systematically investigates the effect of highly oxidative environments on ORR electrochemical behavior.It demonstrates the strategy for facilitating oxygen electrocatalytic activity and stability of the atomically dispersed M-N-C catalysts.

关键词： atomically dispersed Fe-N-C catalysts ORR/OER Rechargeable zinc-air battery Fuel cells