In situ redox growth of mesoporous Pd-Cu2O nanoheterostructures for improved glucose oxidation electrocatalysis  

作　　者：Ying Guo Jianwen Liu Yi-Tao Xu Bo Zhao Xuewan Wang Xian-Zhu Fu Rong Sun Ching-Ping Wong 

机构地区：[1]Shenzhen Institutes of Advanced Technology,Chinese Academy of Sciences. Shenzhen 518055,China [2]Department of Materials Science and Engineering,City University of Hong Kong,Hong Kong,China [3]College of Materials Science and Engineering,Shenzhen University,Shenzhen 518055,China [4]National Supercomputing Center in Shenzhen,Shenzhen 518055,China [5]Department of Electronics Engineering,The Chinese University of Hong Kong,Hong Kong,China [6]School of Materials Science and Engineering,Georgia Institute of Technology,Atlanta,GA 30332,USA

出　　处：《Science Bulletin》2019年第11期764-773,共10页科学通报（英文版）

基　　金：supported by the National Natural Science Foundation of China(21203236);Guangdong Department of Science and Technology(2017A050501052);Shenzhen Research Plan(JCYJ20160229195455154)

摘　　要：Interfaces of metal-oxide heterostructured electrocatalyst are critical to their catalytic activities due to the significant interfacial effects. However, there are still obscurities in the essence of interfacial effects caused by crystalline defects and mismatch of electronic structure at metal-oxide nanojunctions. To deeply understand the interfacial effects, we engineered crystalline-defect Pd-Cu2O interfaces through nonepitaxial growth by a facile redox route. The Pd-Cu2O nanoheterostructures exhibit much higher electrocatalytic activity toward glucose oxidation than their single counterparts and their physical mixture,which makes it have a promising potential for practical application of glucose biosensors.Experimental study and density functional theory(DFT) calculations demonstrated that the interfacial electron accumulation and the shifting up of d bands center of Cu-Pd toward the Fermi level were responsible for excellent electrocatalytic activity. Further study found that Pd(3 1 0) facets exert a strong metaloxide interface interaction with Cu2O(1 1 1) facets due to their lattice mismatch. This leads to the sinking of O atoms and protruding of Cu atoms of Cu2O, and the Pd crystalline defects, further resulting in electron accumulation at the interface and the shifting up of d bands center of Cu-Pd, which is different from previously reported charge transfer between the interfaces. Our findings could contribute to design and development of advanced metal-oxide heterostructured electrocatalysts.Interfaces of metal-oxide heterostructured electrocatalyst are critical to their catalytic activities due to the significant interfacial effects. However, there are still obscurities in the essence of interfacial effects caused by crystalline defects and mismatch of electronic structure at metal-oxide nanojunctions. To deeply understand the interfacial effects, we engineered crystalline-defect Pd-Cu2O interfaces through nonepitaxial growth by a facile redox route. The Pd-Cu2O nanoheterostructures exhibit much higher electrocatalytic activity toward glucose oxidation than their single counterparts and their physical mixture,which makes it have a promising potential for practical application of glucose biosensors.Experimental study and density functional theory（DFT） calculations demonstrated that the interfacial electron accumulation and the shifting up of d bands center of Cu-Pd toward the Fermi level were responsible for excellent electrocatalytic activity. Further study found that Pd（3 1 0） facets exert a strong metaloxide interface interaction with Cu2O（1 1 1） facets due to their lattice mismatch. This leads to the sinking of O atoms and protruding of Cu atoms of Cu2O, and the Pd crystalline defects, further resulting in electron accumulation at the interface and the shifting up of d bands center of Cu-Pd, which is different from previously reported charge transfer between the interfaces. Our findings could contribute to design and development of advanced metal-oxide heterostructured electrocatalysts.

关 键 词：METAL-OXIDE interfaces CRYSTALLINE defects Interfacial electron ACCUMULATION ELECTROCATALYSTS Density functional theory 

分 类 号：N[自然科学总论]