Bi₂WO₆/Nb₂CT_x MXene hybrid nanosheets with enhanced visible-light-driven photocatalytic activity for organic pollutants degradation

The 2D/2D hybrid photocatalyst of ultrathin Bi₂WO₆/Nb₂CT_x hybrid nanosheets was synthesized via a facile hydrothermal process. The photocatalytic performance of Bi₂WO₆/Nb₂CT_x hybrid nanosheets for the degradation of rhodamine B (RhB), methylene blue (MB) and tetracycline hydrochloride (TC-HCl) were investigated. The results showed that the Nb₂CT_x nanosheets greatly improved the separation efficiency of photogenerated carriers and the photocatalytic activity of Bi₂WO₆. Compared with Bi₂WO₆, Bi₂WO₆/Nb₂CT_x hybrid nanosheets photocatalysts exhibited excellent photodegradation efficiency for RhB (99.8%), MB (92.7%) and TC-HCl (83.1%), respectively. The photodegradation rate constants of Bi₂WO₆ coupled with 2 wt% Nb₂CT_x for RhB and MB were 0.072 min⁻¹ and 0.0285 min⁻¹, which were 2.8 times and 2 times as high as that of pristine Bi₂WO₆, respectively. In addition, the photodegradation rate constant of Bi₂WO₆ coupled with 2 wt% Nb₂CT_x for TC-HCl reaches 0.0171 min⁻¹. This study provided an efficient photocatalyst with 2D/2D structures and demonstrated that 2D Nb₂CT_x is a promising co-catalyst to improve the photodegradation performance of photocatalysts.