Enhanced visible light photocatalytic activity of CdS with alkalized Ti3C2 nano-sheets as co-catalyst for degradation of rhodamine B

Active co-catalysts have been extensively used for improving photocatalytic activity in semiconductor-based photocatalytic systems. Herein, 2D alkalized Ti3C2 (Ti3C2-OH) nano-sheets were coupled with CdS via a facile electrostatic self-assembly strategy and combined with hydrothermal method to prepare Ti3C2-OH/CdS photocatalyst. The morphologies, crystal phases, optical and photoelectrical properties of the prepared photocatalysts were characterized by XRD, SEM, TEM, FTIR, PL, and EIS analysis, respectively. The photocatalytic degradation results verified that the photo-degradation performance of Ti3C2-OH/CdS photocatalyst (degradation of 97% RhB in 100 min) was obviously superior to that of pure CdS (degradation of 70% RhB in 100 min) and Ti3C2/CdS (degradation of 82% RhB in 100 min). The active species trapping experiments for Ti3C2-OH/CdS photocatalyst revealed that the superoxide radical (O-center dot(2)-) and holes (h(+)) were the predominant species for degradation of RhB. Furthermore, the Ti3C2-OH co-catalyst in the Ti3C2-OH/CdS composite not only played the role of promoting the effective separation of photo-generated electron-hole pairs, but also constructing strong connections with CdS semiconductor to establish heterostructure, ultimately enhancing the photocatalytic performance of the Ti3C2-OH/CdS photocatalyst.