One-pot synthesis of CdS nanoparticles with surface-phase junctions to catalyze the photo-reduction of CO2 into CO and CH4 selectively

Without any external template & surfactant , CdS nanoparticles (NPs) with surface-phase junctions were synthesized directly from CdCl 2 and the CS 2 -storage material (CS 2 SM) with a simple one-pot strategy, in which only stirring was needed. Under visible light irradiation, the as-synthesized CdS NPs could selectively catalyze the reduction of CO 2 to produce CO and CH 4 sustainably with a perfect catalyst stability even after 33 h. At 4 °C and the optical power density of 370 mW/cm 2 , the as-synthesized CdS NPs from 0.5 g CS 2 SM exhibited 195.41 μmol/g cat CH 4 generation capacity and the 9.01 μmol·g cat −1 ·h −1 maximum average yield, in which the generation ratio of CH 4 /CO was at 8:2; and the as-synthesized CdS NPs from 2.0 g CS 2 SM exhibited 119.95 μmol/g cat CO generation capacity and the 3.75 μmol·g cat −1 ·h −1 maximum average yield, in which the generation ratio of CH 4 /CO was at 1:3. The research results indicated that CdS NPs with higher hexagonal content and smaller particle size is more active in CO 2 photoreduction, which may be due to the low potential CdS NPs surface phase junction reducing the recombination rate of electron hole pairs and improving photocatalytic activity. The simple preparation of CdS NPs and their further photocatalytic CO 2 reduction provide a green and sustainable foundation for the application of sulfide photocatalysts .