Recent developments and perspectives of Ti-based transition metal carbides/nitrides for photocatalytic applications: A critical review

Two-dimensional transition metal carbides/nitrides (MXenes) hold significant promise across diverse domains such as energy, catalysis, environmental science, and life sciences due to their distinct physical and chemical properties. This review focuses on the utilization of Ti-based MXenes specifically for photocatalytic applications. It critically evaluates the structural properties, fabrication strategies, and theoretical simulations of Ti-based MXenes tailored for photocatalysis. Firstly, the structural, electronic and optical properties of Ti-based MXenes are highlighted. Secondly, this review compares the merits and demerits of different fabrication techniques, offering a broad overview of fabrication methods for Ti-based MXenes. Afterwards, strategies aimed at enhancing photocatalytic performance, including interface engineering, defect introduction, heteroatom doping, and morphology control, are summarized. Then this review encapsulates the first-principles calculations and in-situ characterizations related to the fabrication process and photocatalytic mechanism of Ti-based MXenes. Furthermore, it extensively explores the emerging applications of Ti-based MXenes in energy, environmental remediation, and biomedicine. Forward-looking perspectives and insights are finally provided to stimulate innovative ideas and research methodologies for the design, synthesis, and integration of Ti-based MXenes into photocatalytic systems.