Restructuring of 4H Phase Au Nanowires and its Catalytic Behavior toward CO Electro-oxidation  

作　　者：Xuxu Ye Bingyu Liu Da Zhou Yan Xia Chen 

机构地区：[1]Department of Chemical Physics and Hefei National Research Center for Physical Science at the Microscale,University of Science and Technology of China,Hefei 230026,China

出　　处：《Chinese Journal of Chemical Physics》2023年第5期533-544,I0001,共13页化学物理学报（英文）

基　　金：supported by the National Natural Science Foundation of China(No.22172151 and 21972131).

摘　　要：Au nanowires in 4H crystalline phase(4H Au NWs)are synthesized by colloid solution methods.The crys-talline phase and surface structure as well as its performance toward electrochemical oxidation of CO be-fore and after removing adsorbed oleylamine molecules(OAs)intro-duced from its synthesis are evaluat-ed by high-resolution transmission electron microscopy(HR-TEM),X-ray diffraction(XRD),underpoten-tial deposition of Pb(Pb-upd)and cyclic voltammetry.Different methods,i.e.acetic acid cleaning,electrochemical oxidation cleaning,and diethylamine replacement,have been tried to remove the adsorbed OAs.For all methods,upon the removal of the adsorbed OAs,the morphology of 4H gold nanoparticles is found to gradually change from nanowires to large dumbbell-shaped nanoparticles,accompanying with a transition from the 4H phase to the face-centered cubic phase.On the other hand,the Pb-upd results show that the sample sur-faces have almost the same facet composition before and after removal of the adsorbed OAs.After electrochemical cleaning with continuous potential scans up to 1.3 V,CO electro-oxida-tion activity of the 4H Au sample is significantly improved.The CO electro-oxidation activi-ty is compared with results on the three basel Au single crystalline surfaces reported in the lit-erature,possible origins for its enhancement are discussed.

关 键 词：Phase engineering Crystalline phase transition 4H phase Au nanowires Pb un-der potential deposition CO electro-oxidation 

分 类 号：TB3[一般工业技术—材料科学与工程]