Recent advances in titanium carbide MXene-based nanotextures with influential effect of synthesis parameters for solar CO₂ reduction and H₂ production: A critical review

Photocatalytic solar to energy conversion is considered an attractive approach for overcoming energy crises and environmental concerns. Recently, titanium carbide (Ti₃C₂) MXenes have been recognized as promising cocatalysts based on their metallic conductivity, excessive active reaction sites, and enlarged surface area. The current review focuses on the properties and applications of Ti₃C₂ MXenes useful in the field of photocatalysis. More specifically, surface modification of Ti₃C₂ MXenes by varying synthesis parameters to get pure materials and also composites with the role of functional groups towards solar energy conversion applications is highlighted in this review. The effect of etching and oxidizing pathways to get an efficient cocatalyst has been discussed in detail. Considering the significant effect of parameters, optimum synthesis conditions such as etchant type, concentration, time and type of intercalant in both the Ti₃C₂ synthesis approaches for improved photoactivity are discussed. Additionally, the surface modification of Ti₃C₂ through oxidation for TiO₂ growth on its surface is deliberated with a detailed discussion on etchant type, concentration, etching time, and environmental factors. The optimum oxidation condition, including temperature, time, and environment for thermal treatment of Ti₃C₂, were also included. Lastly, the review summarizes the conclusion and future perspectives for solar energy conversion applications.