Z-scheme heterojunction of SnS_(2)-decorated 3DOM-SrTiO_(3) for selectively photocatalytic CO_(2) reduction into CH4

The rapid recombination of photoinduced electron-hole pairs as well as the deficiency of high-energy carriers restricted the redox ability and products selectivity.Herein,the heterojunction of SnS_(2)-deco rated three-dimensional ordered macropores(3DOM)-SrTiO_(3) catalysts were in-situ constructed to provide transmit channel for high-energy electron transmission.The suitable band edges of SnS_(2) and SrTiO_(3) contribute to the Z-scheme transfer of photogenerated carrier.The 3DOM structure of SrTiO_(3)-based catalyst possesses the slow light effect for enhancing light adsorption efficiency,and the surface alkalis strontium is benefit to the boosting adsorption for CO_(2).The in-situ introduced SnS_(2) decorated on the macroporous wall surface of 3DOM-SrTiO_(3) altered the primary product from CO to CH4.The Z-scheme electron transfer from SnS_(2) combining with the holes in SrTiO_(3) occurred under full spectrum photoexcitation,which improved the excitation and utilization of photogene rated electrons for C02 multi-electrons reduction.As a result,(SnS_(2))3/3 DOM-SrTiO_(3) catalyst exhibits higher activity for photocatalytic CO_(2) reduction to CH4 compared with single SnS_(2) or 3 DOM-SrTiO_(3),i.e.,its yield and selectivity of CH4 are 12.5μmol g^(-1) h^(-1) and 74.9%,re spectively.The present work proposed the theoretical foundation of Z-scheme heterojunction construction for enhancing photocatalytic activity and selectivity for CO_(2) conversion.