ZnO-based catalysts have been widely used in hydrogenation reactions,but less attention has been paid to the electrocatalytic hydrogenation process on ZnO electrodes.In this work,the preparation of hydrogen species an...ZnO-based catalysts have been widely used in hydrogenation reactions,but less attention has been paid to the electrocatalytic hydrogenation process on ZnO electrodes.In this work,the preparation of hydrogen species and the associ-ated reduction properties under electrochemi-cal processes in aqueous solutions have been in-vestigated on ZnO and Au/ZnO electrodes.The measurements of cyclic voltammetry(CV),X-ray diffraction,and electron paramagnetic resonance(EPR)confirm the formation of hydro-gen species on the interstitial sites(Hi)or on the oxygen vacancy sites(H_(O)).The hydrogena-tion reaction of p-nitrophenol(pNP)at 40μmol/L occurs on both ZnO and Au/ZnO elec-trodes,and the hydrogenation reduction performance of Au/ZnO electrode is better than that of ZnO electrode.CVs show H_(O)species is much more reactive with pNP than Hi species.Compared with the ZnO electrode,the presence of Au on ZnO promotes the formation of H_(O)species and improves the electro-reduction performance to pNP.These results help us to un-derstand the reaction processes related to the electrochemical hydrogenation on ZnO and Au/ZnO surfaces and shed new light on the design of new catalytic hydrogenation systems.展开更多
基金supported by the National Key Re-search and Development Program of China(No.2021YFA1500403)the National Natural Science Foundation of China(No.21773047 and No.U1832180)partially carried out at the USTC Center for Micro and Nanoscale Research and Fabrication.
文摘ZnO-based catalysts have been widely used in hydrogenation reactions,but less attention has been paid to the electrocatalytic hydrogenation process on ZnO electrodes.In this work,the preparation of hydrogen species and the associ-ated reduction properties under electrochemi-cal processes in aqueous solutions have been in-vestigated on ZnO and Au/ZnO electrodes.The measurements of cyclic voltammetry(CV),X-ray diffraction,and electron paramagnetic resonance(EPR)confirm the formation of hydro-gen species on the interstitial sites(Hi)or on the oxygen vacancy sites(H_(O)).The hydrogena-tion reaction of p-nitrophenol(pNP)at 40μmol/L occurs on both ZnO and Au/ZnO elec-trodes,and the hydrogenation reduction performance of Au/ZnO electrode is better than that of ZnO electrode.CVs show H_(O)species is much more reactive with pNP than Hi species.Compared with the ZnO electrode,the presence of Au on ZnO promotes the formation of H_(O)species and improves the electro-reduction performance to pNP.These results help us to un-derstand the reaction processes related to the electrochemical hydrogenation on ZnO and Au/ZnO surfaces and shed new light on the design of new catalytic hydrogenation systems.
