Low charge separation efficiency is the critical limitation for solar-driven CO2 conversion into chemicals fuels. Accelerating charge transfer in the interface of photocatalysts is an intriguing approach to suppress charge recombination. Herein, Co2+ doped 0D/2D TiO2 quantum dots confined in graphitic carbon nitride (CoTiCN) heterostructure was prepared by in-situ pyrolysis of MOFs and urea. Co2+ serves as the bridge of linking 0D TiO2 and 2D g-C3N4 in the interface, and consequently accelerates charge transfer in the interface from 2D g-C3N4 to 0D TiO2. As a result, CO evolution rate for photocatalytic CO2 reduction reached 290 μmol g-1 h-1, much higher than those of pure g-C3N4 and TiO2/g-C3N4. In addition, photocatalytic mechanism study indicates that [Co(bpy)3]Cl2 in the system functions as cocatalyst without any photocatalytic activity under visible light irradiation. Electron transfer occurs from heterogeneous photocatalyst to [Co(bpy)3]Cl2, which acts as the electron transporter as active sites to catalyze CO2 reduction into CO. This work provides an insight into the design of metal doped 0D/2D material towards visible light driven CO2 reduction from the viewpoint of promoting charge transfer in the interface and the understanding of the photocatalytic mechanism of cocatalyst in system.
All Science Journal Classification (ASJC) codes
- Chemical Engineering (miscellaneous)
- Waste Management and Disposal
- Process Chemistry and Technology