Structure Optimization Of CoO Nanowires Array For Electrocatalytic Hydrogen Evolution And Oxygen Evolution Reaction

The development of new environmentally friendly catalytic materials with excellent performance is the key to solving present energy and environmental problems.Optimization of the catalyst structure is an effective way to enhance the catalytic activity.In the early stage,the team has used the ion replacement strategy to prepare CoO nanorods with special structure.The paper optimizes its structure and applies it in electrochemical hydrogen evolution(HER)and oxygen evolution(OER)electrocatalysis.The specific research results are as follows:Firstly,the controlled growth of Ru NPs with particle size of about 3 nm and(FCC)phase was successfully achieved on CoO NRs,which is more reactive than(HCP)phase Ru.There are strong atomic and electronic coupling between Ru NRs and CoO NRs.The overpotential of the composite catalyst in alkaline environment at current density of 10 m A cm^-2 is 55 m V,which is comparable to commercial Pt/C catalytic performance.In addition,the strong interaction between Ru NPs and CoO NRs and the in-situ growth of CoO support on conductive substrate carbon fibers ensure long-term stability of Ru NPs/CoO NRs hybrid electrocatalyst during the catalytic process.Secondly,uniformlly V doping in CoO NRs improves the conductivity of the CoO and promotes the formation of Co(IV)active site during OER,which is beneficial to the reduction of intermediates formation barrier.When the current density is 10 m A cm^-2,the overpotential of the catalyst is 414 m V,the corresponding Tafel slope is 129m V dec^-1,and the current is only attenuated by 5%after reacting for 20 h at 414 m V overpotential,which exhibits excellent catalytic performance in neutral OER catalysis.