Abstract:

Over the past decade, the surging interest for higher-energy-density, cheaper, and safer battery technology has spurred tremendous research efforts in the development of improved rechargeable zinc-air batteries. Nonetheless, there are still challenges to solve in these Zn-based devices, with the sluggish kinetics of the oxygen reactions (reduction during discharge, evolution during charge) being the limiting step. To date, noble platinum (Pt) and its derivatives exhibit the most effective activities for ORR, while Ir and Ru-based catalysts deliver high catalytic activities for OER. However, their low multifunctional performances which hardly boost various reactions by one electrode, highly restrict their application in Zinc-air batteries. Thus, it is imperative to develop the low-price and bifunctional electrocatalysts with component-structure features, such as abundant active sites serving for two reactions, strong interfacial conjugation, and large electrochemical surface area. Emerging as a kind of earth-abundant materials, transition metal-based materials form a set of economic and environmental electrocatalysts, in which the spinel oxides have been reported in the field of OER and ORR. However, their performance is still far from the requirements of practical applications. With this demand, a universal modification strategy, which can be beneficial for those catalytic processes, is of great importance. Doping with multiple metal ions into spinel material can be an efficient way to enhance the catalytic properties. In this talk, I will give an introduction of electrocatalysts for Zinc-air batteries. Further, I will present the preliminary results of bifunctional electrocatalysts designed by spinel oxides.