Preparation of CdS-P25/ZIF-67 composite material and its photocatalytic CO2 reduction performance

Commercial TiO2 (P25) is a potentially promising catalyst for photocatalytic CO2 reduction. Nonetheless, the inefficient light capture ability and egregious charge recombination restrict its further utilization. In this work, CdS and P25 are incorporated to form the composite CdS-P25, which is further immobilized on the surface of a copper-based organic metal framework (MOF), ZIF-67, so as to establish a ternary hybrid CdS-P25/ZIF-67 via a facile hydrothermal method. On the basis of the enhancement in light absorption resulted from the formation of CdS-P25, the incorporation of ZIF-67 further prolongs the light absorption edge of CdS-P25/ZIF-67, up to 552 nm. In addition, the introduction of ZIF-67 with the dual Z-Scheme system constructed could significantly suppress the charge recombination, as revealed by the transient photocurrent value of CdS-P25/ZIF-67, which is 3.47 μA cm−2, about 20.4 times than that of CdS-P25. Accordingly, the photocatalytic assessment of CdS-P25/ZIF-67 also presents a significantly amelioration in CO2 reduction reaction (CO2RR) in comparison with either CdS-P25 or ZIF-67, giving 1.58 μmol h−1 CH4 and 1.49 μmol h−1 CO production. Our work sheds light on the investigation of efficacious construction of P25 based hybrids for light-driven photocatalysis.