It　is　highly　desirable　but　challenging　to　optimize　the　electronic　structure　of　an　active　site　to　realize　moderate　active　site-H-ads　bond　energies　for　boosting　photocatalytic　H-2　evolution.　Herein,　an　interfacial　engineering　strategy　is　developed　to　simultaneously　concentrate　hydrogen　species　and　accelerate　the　combination　of　an　H-ads　intermediate　to　generate　free　H-2　by　constructing　W-WC-W2C　(WCC)　cocatalysts.　Systematic　investigations　reveal　that　hybridizing　with　W2C　creates　electron-rich　W　active　sites　and　effectively　induces　the　downshift　of　the　d-band　center　of　W　in　WC.　Consequently,　the　strong　W-H-ads　bonds　on　the　surface　of　WC　are　weakened,　thus　promoting　the　desorption　of　H-ads　to　rapidly　produce　free　H-2.　The　optimized　40-WCC/CdS　photocatalyst　exhibits　a　high　hydrogen　evolution　rate　of　63.6　mmol　g(-1)　h(-1)　under　visible　light　(＞=　420　nm)　with　an　apparent　quantum　efficiency　of　39.5%　at　425　nm　monochromatic　light,　which　is　about　40-fold　of　the　pristine　CdS.　This　work　offers　insights　into　the　design　of　cocatalyst　for　high-efficiency　photocatalytic　H-2　production.