Formation of quasi-core-shell In2S3/anatase TiO2@metallic Ti3C2Tx hybrids with favorable charge transfer channels for excellent visible-light-photocatalytic performance

Semiconductor-based heteroj unctions, widely applied in photocatalytic solar-to-chemical energy conversion, are advantageous for synergistically expediting photocatalytic reaction beyond individual the constituent components. Here we showed new quasi-core-shell ln(2)S(3)/anatase TiO2@metallic Ti3C2Tx hybrids consisting of well designed type-II heterojunction and non-noble metal-based Schottky junction with favorable charge transfer channels for efficient photocatalysis application. The mesoporous hybrids owned pleasurable visible-light absorption property and excellent capability in photogenerated exciton separation and carrier transport. Specifically, the hybridized photocatalyst with the additive Ti3C2Tx content of 16 mg (InTi-16) had excellent visible-light photocatalytic performance towards pollutant removal in water with a degradation rate of 0.04977 min(-1), which was 3.2 and 6.2 folds higher than that of pure ln(2)S(3) and pure Ti3C2Tx, respectively. What's more, the photocatalytic degradation ability of InTi-16 had surpassed that of many other types of In2S3-based photocatalyst including In2S3/carbon nanotube (CNT), In2S3/reduced graphene oxide (rG0), In2S3/MoS2, and In2S3/TiO2 hybrids. The promising photocatalytic performance was strongly depended on the separation and diffusion of photogenerated exciton and carrier via a multitude of charge transfer channels due to the formation of double heterostructure (type-II heterojunction and Schottky junction). It had originated from the synergistic effects among the visible-light absorption of In2S3, the upward band bending of TiO2 and the favorable electrical conductivity of Ti3C2Tx. Prolonger electron lifetime favored for the generation of more strongly oxidizing radical (e.g. -O-2-) at the in-plane of Ti3C2Tx, and thus enhanced photocatalytic degradation ability. This work demonstrates that the TiO2/Ti3C2Tx can be a potentially novel platform for constructing efficient photocatalysts both for wide-ranging applications and unraveling the transfer behavior of photo-excited electrons based on charge transfer channels.