CsTaWO6 as photoelectron platform by carbon nitride sensitizing toward enhanced charge carrier separation and photocatalytic activity

A series of CsTaWO 6 /g-C 3 N 4 composite photocatalysts were successfully prepared aiming to regulate the charge kinetics for spatial separating the photoinduced electrons and holes under visible light irradiation, which was ascribed to the matched band edge alignment of CsTaWO 6 and g-C 3 N 4 . Careful characterization on the as-prepared photocatalysts indicated the co-existent of g-C 3 N 4 and CsTaWO 6 in the composite. Because of electronic structure match and fine interfacial contact, CsTaWO 6 anchored with g-C 3 N 4 can enhance the visible light harvesting capacity and the photocatalytic activity toward hydrogen evolution was greatly improved with an optimized evolution rate of 7.5 μmol·g −1 ·h −1 and an excellent photocatalytic stability was achieved. The enhancement of photocatalytic activity was attributed to the fact that photoinduced electrons in the conduction band of g-C 3 N 4 can be efficiently injected into the conduction band of CsTaWO 6 , leading to spatial charge separation between g-C 3 N 4 and CsTaWO 6 , which can be confirmed by incident photocurrent responses and electrochemical impedance curves. Graphical abstract The charge kinetics for the spatial isolation of photogenerated charge carrier and the visible light harvesting capacity were enhanced by constructing CsTaWO 6 /g-C 3 N 4 composite photocatalysts, leading the photocatalytic activity toward hydrogen evolution improved.