Study On Oxygen Catalytic Performance Of Non-precious Metal-graphene Composites

With the increasing negative impact of air pollution and energy shortage on people’s lives,people’s attention to new types of clean energy is gradually increasing.Metal-air batteries are used as a power generation device to convert chemical energy into electrical energy,due to its high energy conversion efficiency and environmental friendliness,it has attracted people’s attention.The oxygen reduction reaction occurring on the air electrode is one of the key factors affecting the performance of the battery,and the oxygen reduction reaction rate is affected by the performance of the catalyst.Therefore,it is great significance to develop a catalyst material with high activity and high stability.In this paper,a series of graphene-based catalyst materials prepared by graphene have good conductivity,large specific surface area and high catalytic activity,and the properties of the composites are tested and characterized by various testing methods.In this paper,Mn₃O₄/rGO composites were prepared in high temperature and high pressure environment.It was found that the amount of manganese acetate,reaction time and reaction temperature had certain effects on the morphology and catalytic activity of the prepared composites.It was found that the reaction time was controlled to 8 hours,the reaction temperature was controlled to 160°C,and the raw material dosage was controlled to be GO:manganese acetate=1:8,the prepared composite material had the best performance.The composite material prepared under the reaction conditions has a peak potential of-0.435V,which has higher catalytic activity and lower electrical resistance than the composite prepared under other conditions.At the same time,Ag/rGO and Ag-Mn₃O₄/rGO composites were prepared,and the performance of the composites was improved by adjusting the ratio of raw materials.The prepared Ag-Mn₃O₄/rGO composite material makes Mn₃O₄ and Ag nanoparticles evenly distributed on the surface of rGO,and the oxygen reduction peak position is-0.115V,which is obviously positively offset and the peak current is also significantly increased compared with other composite materials.In addition,by improving the preparation process of the air electrode,the stability of the electrode is prolonged and the working time of the electrode is prolonged.The open circuit voltage of the assembled magnesium-air battery can reach 1.57V,stable working time can reach 22 days and can realize functions such as charging lithium battery.