Phase modulation of 1T/2H MoSe2 nanoflowers for highly efficient bifunctional electrocatalysis in rechargeable Li–O2 batteries

Abstract

Li–O₂ batteries with outstanding energy density are considered to be promising next-generation power sources for various future electric devices. However, the battery performance is limited by the inferior electrocatalytic activity of catalysts in the cathode. In this work, MoSe₂ catalysts with hybrid 1T and 2H phases were prepared through an efficient two-step hydrothermal strategy. The combination of the 1T phase with the 2H phase could synergically enhance the catalytic activities towards both oxygen reduction reaction and oxygen evolution reaction, and the built-in heterojunction between them also dramatically facilitated the interfacial charge transfer kinetics. Additionally, the hierarchical flower-like architecture with multidimensional channels would promote the rapid electron and mass diffusion, as well as provide enough space for storing discharge products. Thanks to the above merits, MoSe₂ cathodes delivered improved electrocatalytic properties for Li–O₂ batteries. This present work may pave a new avenue for highly efficient bifunctional electrocatalyst construction for Li–O₂ batteries.