Confining single Pt atoms from Pt clusters on multi-armed CdS for enhanced photocatalytic hydrogen evolution

It is extremely desirable to effectively exploit photo-excited electrons for achieving highly efficient photocatalytic hydrogen production. Herein, atomically dispersed platinum clusters are developed as a novel single atom co-catalyst, which dramatically enhances the photocatalytic H-2 production rate. Under visible-light irradiation, a maximum value of 13.0 mmol g(-1) h(-1) is reached. Synchrotron radiation-based X-ray absorption fine structure (XAFS) spectroscopy verifies that the Pt clusters are uniformly anchored on the surface of multi-armed CdS nanorods with Pt-S-4 active sites. Ultrafast transient absorption (TA) spectroscopy clearly reveals that atomically dispersed platinum can quickly extract the photo-generated electrons of CdS nanorods. Density functional theory (DFT) calculations further demonstrate the superiority of monatomic platinum as a co-catalyst. This work provides a new approach for preparing single atom co-catalysts from clusters for photocatalysts with high photocatalytic performance.