Ag and TiO2 nanoparticles co-modified defective zeolite TS-1 for improved photocatalytic CO2 reduction.

Photocatalytic CO2 reduction into fuels has been an attractive research topic. Herein, Ag and TiO2 nanoparticles co-loaded zeolite TS-1 (Ag-TiO2/TS-1) were synthesized by the ion-exchange and subsequently in-situ photodeposition method. The obtained Ag-TiO2/TS-1 sample has a high surface area and rich Ti3+-Vo defects and as well as highly dispersed Ag nanoparticles. As expected, the sample Ag-TiO2/TS-1 not only shows high CO2 adsorption capacity, but also improves the separation efficiency of photogenerated electron-hole pairs. As a result, only CO and CH4 can be detected on the sample Ag-TiO2/TS-1 in the photocatalytic CO2 conversion, and the competing H2 evolution can be completely suppressed, suggestive of its high selectivity. The super photocatalytic activity toward CO2 reduction can be ascribed to the synergistic effect among highly dispersed Ag nanoparticle, the support zeolite TS-1 and TiO2 with highly exposed {101} planes.