Application of MXene-based materials in hybrid capacitors

Abstract

MXenes, a noble category of 2D transition metal carbides or nitride-layered materials, exhibit special electroconductibility in a crystal nucleus, low-energy barriers for metal ion diffusion, satisfactory layer spaces for ion intercalation and abundant functional groups (e.g., –F, –OH and –O) exhibiting special electroconductibility on their surfaces. These characteristics have introduced several possibilities for manufacturing state-of-the-art MXene-based materials for hybrid capacitors with excellent energy density, high power density and long lifespan. This article reviews the research progress on MXene-based materials for hybrid capacitors with different anodes and cathodes. Firstly, the energy storage mechanism of hybrid capacitors and the preparation of MXene materials are briefly introduced. Secondly, the strategy of modifying MXene-based materials to construct high-performance hybrid capacitors is emphasized. Finally, some challenges and opportunities of using MXene-based materials in hybrid capacitors are outlined.