高密度CoNC位点负载碳催化剂的制备及氧还原性能OA

Developing high-performance electrocatalysts to improve the Oxygen Reduction Reaction(ORR)efficiency on the cathode surface is of great significance to improving the energy conversion ef-ficiency of metal-air batteries.In this work,a porphyrin-based Metal-Organic Framework(Co-TPyP MOF)was first synthesized as a precursor by using a solvothermal method,and then CoNC-P series electrocatalysts were prepared through high-temperature carbonization and phosphorus doping.SEM,TEM,XRD,BET and other technical means were used to characterize the morphology,structure and physical and chemical characteristics of these catalysts.Electrochemical performance experiments show that the ORR half-wave potential and limiting current density of the optimized CoNC-P-5 sample are as high as 0.861 V and 4.15 mA/cm2 in 0.1 mol/L KOH electrolyte,respectively,even exceeding the commercial Pt/C catalyst with mass fraction of 20%,which may mainly benefit from the high density of dispersed Co sites and developed pore structure in the catalyst,significantly shortening the mass transfer path and improving the utilization of active sites.Electron transfer number measure-ment demonstrated that the catalytic ORR has high 4e process selectivity.In addition,in the continu-ous 36 000 s test,the ORR current retention rate was as high as 93.8%,indicating excellent stability of CoNC-P-5 catalyst.article,it must not contain results which are not presented and substantiated in the main text and should not exaggerate the main conclusions.