Study On Preparation Of Modified Of Cobalt Oxide Nanofiber Electrodes By Electrospinning

With the continuous increase of energy demand and the continuous consumption of non-renewable energy reserves,it is particularly important to improve the conversion rate of energy to deal with the future energy crisis.The study of high-efficiency energy conversion devices can alleviate the excessive dependence on energy to a certain extent.Zinc-air battery is one of the important energy conversion devices,and its charge-discharge efficiency depends on the oxygen reduction and oxygen evolution reactions,but these two reactions are limited by the slow chemical reaction kinetics and cannot achieve more efficient energy conversion.In order to break through this limitation,a large number of studies have been focused on the improvement of catalyst performance,and remarkable research results have been achieved.Among them,cobalt oxide materials are not only abundant in reserves,but also show good performance in oxygen reduction and oxygen evolution reactions,so they are favored by researchers.However,due to its lack of electrical conductivity,its catalytic performance still has a certain room for improvement.In order to improve the cobalt oxide material and improve its catalytic performance,the cobalt oxide nanofiber electrode was prepared by electrospinning method,and the cobalt oxide was improved by doping with ruthenium and palladium respectively.Combined with the unique structural advantages of the doping process and the small size and large aspect ratio of the one-dimensional structure,the catalytic performance of the cobalt oxide material has been further improved,thereby increasing the energy conversion rate.The specific experiments and research results are as follows:(1)Coral-like ruthenium-doped cobalt oxide(Ru-Co3O4)nanofibers and undoped cobalt oxide(Co3O4)nanofibers were successfully prepared by electrospinning.The prepared Ru-Co3O4 nanofibers were composed of nanoparticles are connected,with pores conducive to catalytic performance and channels conducive to rapid electron transport.Therefore,Ru-Co3O4 exhibits comparable oxygen reduction performance to commercial platinum/carbon(Pt/C)and superior oxygen evolution performance to ruthenium oxide(RuO2)in alkaline environment.Furthermore,this shows a significant improvement in the bifunctionality of Ru-doped Co3O4 nanofibers compared to undoped Co3O4 nanofibers.The phase,morphology and structure of the Ru-Co3O4 nanofiber electrode after the stability test were characterized,and the Ru-Co3O4 nanofiber electrode still showed good structural stability.(2)On the basis of(1),the Co3O4 material is doped with ruthenium replaced by palladium.In addition,combined with the excellent carrier advantages of one-dimensional carbon nanofibers,a palladium-doped cobalt oxide-supported carbon nanofiber(Pd-Co3O4@CNF)material was designed.Pd-Co3O4@CNF was successfully prepared by electrospinning combined with suitable heat treatment conditions obtained from many attempts.This is different from powder catalysts.Our synthetic materials are directly cut into regular shapes(without the need to prepare electrode ink),and the catalytic performance can be tested directly.It exhibits enhanced bifunctional catalytic performance and long-cycle stability.It was assembled into a zinc-air battery,which still showed good performance.