Ti-based MXenes for Energy Storage Applications: Structure, Properties, Processing Parameters and Stability

The novel family of two-dimensional transitional metal carbides, nitrides and carbonitrides (Also known as MXenes) is being considered as the next generation of materials because of their unique properties and vast potentiality as the active material in different field of applications, such as sensors, energy storage devices, energy generators, EMI shields etc. Among them, MXenes have great prospects in electrochemical energy-storage application. MXenes show unique properties due to their low dimensional, layered structure which are convenient for energy storage applications. Theoretically, MXenes have high mechanical strength, competitive gravimetric capacitance, and outstanding catalytic properties. However, the advancement of MXenes towards industrial manufacturing is impaired because of poor mechanical and electrochemical properties of experimentally obtained films, poor stability in oxygen rich environment, and lack of scaled-up production protocols. Hence, to fully utilize the outstanding prospects of this novel material, it is important to understand the structure-property relationship, effect of processing parameters, environmental stability, and scale-up scopes of MXenes. In the perspective, this article reviews the structural, electrochemical, and mechanical properties of MXenes, and strategies to control the properties for application-specific requirements. The relationships between synthesis parameters and the properties of MXenes are discussed. Oxidation stability and the proposed strategies to improve shelf-life are also reviewed.