Carbon aerogel supported Pt–Zn catalyst and its oxygen reduction catalytic performance in magnesium-air batteries

Our research aims at exploring a new oxygen reduction reaction (ORR) catalyst with effective catalytic capability, which can be used in the metal-air batteries. ORR electrocatalysts of carbon black and carbon aerogel supported Pt-based nanoparticles were synthesized by a chemical impregnation reduction method. The electrochemical measurement consisted of cyclic voltammetry (CV) and line scan of scanning electrochemical microscopy (SECM) conducted in alkaline medium as well as the single-cell tests. All the tests indicate that the Pt–Zn/carbon aerogel (Pt–Zn/CA) catalyst, with the specific discharge capacity reaching 1349.5 mA h g−1, exhibits the best catalytic performance among all the tested catalysts. The doping of Zn forms Pt-rich surface, creates more d-band vacancies, and reduces the leaching problem; the use of carbon aerogels brings larger specific surface area. These aspects have all improved the catalytic activity per unit mass.