Review on Ti3C2 MXene-based binary and ternary composites for photocatalytic applications

Abstract

2D layered materials have been employed as suitable co-catalysts for many photocatalytic reactions owing to their numerous advantages, such as high specific surface area, surface-active sites and suitable surface acid–base properties. Materials, such as graphene, MoS₂, black phosphorous and MXenes, have been extensively explored in this regard, with MXenes gaining tremendous interest. MXenes not only mediate the charge carrier transfer pathways when conjugated with semiconductors but also act as excellent precursors to obtain the respective metal oxides at a moderate annealing temperature. Given that titania is the gold standard photocatalytic material, initially, this review presents the design and fabrication of Ti₃C₂/TiO₂ from the viewpoint of both preparation methods and applications towards pollutant degradation and hydrogen evolution reactions. Subsequently, Ti₃C₂/TiO₂-based ternary composite comprising superior nanomaterials, such as BiOX, AgX, g-C₃N₄, metal sulphides, metal oxides, quantum dots and metal particles, are emphasized to demonstrate their advancements. Alternatively, the photocatalytic applications of C@TiO₂ obtained from the complete oxidation of Ti₃C₂ and the related ternary systems are emphasized. The charge carrier dynamics specific to the heterostructure and participation of free radicals in the pollutant degradation mechanism are highlighted at the respective stages. Finally, the associated challenges and future perceptions of Ti₃C₂-based heterostructures are emphasized for broader applications.