Synthesis of Z-scheme α-Fe2O3/g-C3N4composite with enhanced visible-light photocatalytic reduction of CO2to CH3OH

•Z-scheme α-Fe2O3/g-C3N4composites were rationally fabricated.•The α-Fe2O3/g-C3N4showed highly efficient photoreduction performance of CO2.•The introduction of α-Fe2O3enhanced the absorption of visible light.•The possible photoreduction mechanism over α-Fe2O3/g-C3N4composite was discussed.•The Z-scheme heterostructure promoted photogenerated electron and hole separation.•The Z-scheme heterostructure suppressed the recombination of photoexcited electron-hole pairs.