Optimization of d-p band centers as efficient active sites for solar energy conversion into H2 by tuning surface atomic arrangement

The lowered reaction energy barrier and accelerated dynamic behavior for photocatalytic HO overall splitting (HOS) involving oriented chemisorption, activation and conversion of *H and oxyhydrogen intermediates are crucial for solar energy conversion into H (STH). Herein, the localized heterojunction (Cd-S-Ni) composed of NiS and CdS tuning surface atomic arrangement with S atoms as the shared ligands has been constructed to synchronously elevate and optimize Ni 3 (Ni ) and S 2 (S ) band centers as efficient active sites for chemisorption of oxyhydrogen and *H intermediates with a declined Cd 4 band center (Cd ) to suppress reverse reaction. A sustainable STH of 3.21 % under AM 1.5 G has been completed over Cd-S-Ni with a decreased activation energy for H evolution, verified by fs-TAS, DRIFTS and dynamic DFT. These results devote to solving the reaction energy barrier and dynamical bottleneck for HOS by optimizing and .