Effect of water intercalation into tungsten trioxide structure (WO3·xH2O) (x = 0,1,2): Correlation between structure and photocatalytic performances

•Band-gap engineering using water intercalation into tungsten oxide structure.•The effect of water intercalation on photocatalytic performance: efficiency and resistance to the photocorrosion.•The studied materials were used as a potential photocatalysts for pollutant degradation and water oxidation.