Insights into MXenes-based electrocatalysts for oxygen reduction

Due to the urgent need for a sustainable energy economy, fuel cells, which use clean and renewable fuels (hydrogen and methanol) for efficient power generation, have attracted more and more attention in recent years. The oxygen reduction reaction(ORR) on the cell's cathode is the core of its electrochemical conversion process, and the performance of the ORR electrocatalyst determines the overall performance and efficiency of related devices. Developing efficient, durable, and low-cost electrocatalysts for ORR has always been the goal of people's exploration. In recent years, MXenes, a new family of two-dimensional (2D) metal carbides, nitrides, and carbonitrides, have emerged and attracted great interest due to their excellent electrical conductivity and high surface area. The MXene-based materials inspire the design and preparation of electrocatalysts with increased ORR activity, high selectivity, and long load life. This review has provided an overview of MXenes, then described their synthesis methods, and finally explained the progress of MXene (mainly Ti3C2Tx) in the field of oxygen reduction.