MXenes@metal-organic framework hybrids for energy storage and electrocatalytic application: Insights into recent advances

The need to reduce the carbon footprint and to develop clean energy conversion and storage technologies has led to significant research efforts in the design of multifunctional materials. Metal-organic frameworks (MOFs) have become the key materials in this field because of their high specific surface area, tunable pore diameters and high concentrations of active metal sites. However, the suboptimal conductivity of conventional MOFs limits their application in energy storage. The conductivity of MOF has been improved by developing hybrid materials that integrate MOF with various conductive guests. Two-dimensional transition metal carbides and nitrides (MXenes) are a new class of 2D materials, which has remarkable structural diversity and abundant surface chemical properties. Here, we summarize critically the structure and properties of MXenes, MOFs and MXenes@MOFs hybrid materials, and also review the synthesis strategies and characterization methods of MXenes@MOFs hybrid materials, as well as their applications in electrochemical energy storage. Finally, the challenges in developing MXenes@MOFs hybrid materials and their practical applications are revealed, and the challenges in future research fields are addressed.