An overview of non-noble metal electrocatalysts and their associated air cathodes for Mg-air batteries

Abstract Although metal-air batteries (MABs) including Mg-air batteries possess high theoretical energy densities and are promising in energy storage systems, the poor performances and high cost of corresponding electrocatalysts and air cathodes significantly limit practical application. Based on this, the present review gives a summary of the recent progress in the development of cost effective non-noble metal electrocatalysts and their associated air cathodes for MABs, with a particular focus on Mg-air batteries including the aspects of corresponding catalyst synthesis and characterization, catalyzed oxygen reduction reaction (ORR) mechanism, air cathode fabrication and performance validation. The paper also provides an analysis on the issues that challenge the development of advanced electrocatalysts and the associated air cathodes for Mg-air batteries, as well as a discussion of potential research directions that may help resolve these issues and facilitate the practical application of Mg-air batteries