A study of photocatalytic and photoelectrochemical activity of as-synthesized WO3/g-C3N4 composite photocatalysts for AO7 degradation

•The WO3/g-C3N4 composites were prepared by a facile wet impregnation method.•The degradation ability of WO3/g-C3N4 composite was studied by degradation of AO7.•The optimized 3% WO3/g-C3N4 composite showed an efficient photocatalytic activity.•Also, it possesses an excellent photo-stability under visible-light illumination.•So, the WO3/g-C3N4 composite will be a potential material for water purification.