Efficient visible-light-driven CO2 reduction into tunable syngas by cobalt phthalocyanine modified flower-like ZnIn2S4 nanosheets

Photocatalytic carbon dioxide (CO2) reduction into syngas (the mixture of CO and H2) has been considered as an attractive method to solve the greenhouse effect and energy shortage. Polychalcogenides semiconductors such as ZnIn2S4 (ZIS) have been widely utilized in photocatalysis but are still hampered by limited photo-induced charge separation and poor product selectivity. Molecular catalysts for CO2 reduction possess superior selectivity for specific reduction products but suffer from low stability and recycling difficulty. Herein, we modified a molecular phthalocyanine (Pc) on flower-like ZIS nanosheets. This hybrid exhibited enhanced photocatalytic CO2 reduction and exhibited a tunable ratio of CO/H2 in syngas (0.01–4.65) under visible light irradiation. The enhanced photocatalytic activity of ZIS-Pc hybrids can be attributed to dimension-matched ultrathin heterojunction, which facilitated charge separation, broad light utilization, and recycling stability. The unique design holds great potential for other highly efficient photocatalytic reactions.