Carbon dots decorated ultrathin CdS nanosheets enabling in-situ anchored Pt single atoms: A highly efficient solar-driven photocatalyst for hydrogen evolution

Maximizing the usage of cocatalyst to provide fruitful proton reduction sites and suppress charge carrier recombination is an effective stratagy to dramatically improve the photocatalytic performance. Herein, anchoring single atoms (SAs) of Pt onto the ultrathin porous CdS@carbon dots (CDs) nanosheets has been achieved through in-situ reduction of Pt precursor. X-ray absorption fine structure spectra identify that the single Pt atoms are bonded as Pt-S with a coordination number 4, due to the scattering between platinum center and the sulfur atoms. The Pt single atoms exhibit strong capacity to trap photo-generated electrons, rendering CdS@CDs/Pt-SAs as a class of efficient solar-driven photocatalyst. It shows an outstanding activity towards H-2 generation at rate of 45.5 mmol h(-1) g(-1), which is 133 times of that for bare CdS@CDs. The novel method can be extended to the preparation of various functional nanocatalysts owing to its versatility and facileness.