Facile preparation of dual Z-scheme Bi2O3/g-C3N4/Ag6Si2O7 photocatalyst for highly efficient visible-light photocatalytic degradation of organic pollutants

•Bi2O3/g-C3N4/Ag6Si2O7 with dual Z-scheme structure was prepared by a facile method.•The catalyst has superior visible-light photocatalytic activity for MB, RhB and TC.•Dual Z-scheme mechanism well elucidated the excellent photocatalytic performance.•The catalyst shows significant potential for degradation of organic pollutants.