In situ loading of Ag2S particle on Nb2O5 sheets for synergistically enhanced photocatalytic decontamination of methylene blue

Novel p-Ag2S/n-Nb2O5 heterojunction composites were successfully obtained for the first time by hydrothermal and ion-exchange deposition way. A series of photocatalytic tests and characterization results confirm that the optimized 10 wt% Ag2S/Nb2O5 heterojunction composite exhibits excellent photocatalytic degradation activity for methylene blue (92.8%) under simulated solar light irradiation, which is approximately 2.7 times higher than that of pure Nb2O5 (34.3%) and 2.2 times higher than that of Ag2S (42.0%). The outstanding photocatalytic activity of Ag2S/Nb2O5 heterojunction composites could be ascribed to enhance simulated solar light response and effectively accelerates photo-induced charge separation and migration via a Z-scheme mechanism. Furthermore, the trapping experimental results confirm that both superoxide radicals (·O− 2) and hydroxyl radicals (·OH) play a key role in photocatalytic degradation process.