Study On Preparation And Catalytic For Oxygen Reduction Reaction Performance Of Transition Metal Oxide Supported On N-doped Carbon Support

With the progress and development of society,the energy crisis is also intensifying,and the development and rational use of new energy has become very important.Noble metal catalysts represented by Pt/C are commonly used high-efficiency oxygen reduction reaction（ORR）catalysts,but their low reserves and high prices are not conducive to large-scale development and commercial applications.In recent years,carbon-based catalysts have become a research focus due to their low price and abundant sources.Therefore,this paper prepared a series of transition metal oxide supported on N-doped carbon support,and studied the oxygen reduction reaction performance of these catalysts.This paper mainly includes three aspects of research:（1）Preparation of iron-modified carbon aerogel by molten salt method.In this work,the optimized iron-modified carbon aerogel（FCG-2）has a multi-level hole structure,the surface nitrogen content is more than 4 times higher than that of CG,and the ratio of pyridine nitrogen is also significantly increased.Compared with the initial CG,the initial potential of FCG-2 increased by 39 m V,and the half-wave potential increased by 14 m V.Studies have shown that the process of preparing FCG by molten salt method can effectively improve the ORR catalytic activity of CG,and the surface reconstruction of the carbon layer is feasible in improving the catalytic performance of carbon materials.（2）In order to study the effect of rare earth elements on the catalytic ORR performance of FCG,Fe and Ce co-doped carbon aerogels（FCCG）were prepared by Ce doped.In this work,Ce can reduce the Fe₂O₃ nanoparticles.In the ORR performance test,the initial potential of FCCG-2 reached 0.968 V,and the half-wave potential reached0.842 V.The study shows that the addition of Ce element can improve the dispersion of Fe₂O₃ nanoparticles,and when the Ce content is 0.05 mg,the uniformity of FCCG-2 is better.（3）In order to explore whether the replacement of Fe by transition metal Mn can achieve better results,a manganese modified carbon aerogel was prepared by introduing transion metal Mn.In the ORR performance test,the initial potential of MCG-2 reached0.988 V,and the half-wave potential reached 0.859 V.The power density of the assembled zinc-air battery is 112.38 m W cm^-2,which is 9.75 m W cm^-2higher than Pt/C.This study shows that the MCG prepared by replaced Fe with transition metal Mn has excellet ORR performance and has practical application value in zinc-air batteries.