Activation of the WS 2 Inert Plane via W‐Site Regulation Promotes the H 2 Evolution Reaction of the WS 2 /g–C 3 N 4 Photocatalyst

WS 2 , as a potential cocatalyst to enhance the activation of H * , is usually used for H 2 evolution. However, the activity of W atoms in the sandwich WS 2 structure is blocked by the surface S atoms. An in situ F‐induced W‐exposure method is developed to boost the W‐site of WS 2 (W exp ‐WS). W exp ‐WS is anchored on the surface of the porous g‐C 3 N 4 , and then the W exp ‐WS/g‐C 3 N 4 photocatalyst with efficient H * activation is obtained. Particularly, the W‐exposed structure ensures the W coordination number decreases from 5.92 in WS 2 to 5.15 in W exp ‐WS, which improves the H * activation ability of the W‐site and then results in an optimized W‐site Δ G H* (−0.08 kJ mol −1 ). Meanwhile, the II‐type heterojunction promotes the directional transfer of photogenerated electrons from g‐C 3 N 4 to W exp ‐WS. Thus, the H 2 production rate of the W exp ‐WS/g‐C 3 N 4 photocatalyst exhibits 11.97 mmol h −1 g −1 , which is 12 times higher than that of the porous g‐C 3 N 4 .