Single‐Atom Pt Anchoring on Self‐Doped ZrO 2 @G‐C 3 N 4 Nanostructure Enables Efficient Photocatalytic Seawater Hydrogen Evolution

ABSTRACT Solar light‐driven photocatalytic hydrogen generation from seawater can enable sustainable fuel conversion and contribute to decarbonizing energy systems. However, seawater photocatalysis still faces inherent efficiency bottlenecks that demand further exploration. This work develops grain‐like Zr 3+ ‐ZrO 2 and Pt single atom (Pt SA)‐modified step scheme (S‐scheme) Zr 3+ ‐ZrO 2 @g‐C 3 N 4 heterostructures for seawater hydrogen generation under visible‐light irradiation. Experimental results demonstrate that the synthesized Pt SA/Zr 3+ ‐ZrO 2 @g‐C 3 N 4 heterostructures markedly enhanced charge separation and substantially boosted seawater photocatalytic hydrogen production, due to synergistic Pt SA effects and S‐scheme electron transfer pathways. The Pt SA/Zr 3+ ‐ZrO 2 @g‐C 3 N 4 heterojunction achieved a maximum hydrogen evolution rate of approximately 15683.80 µmol g −1 , which was 4.68 times of Pt NPs/Zr 3+ ‐ZrO 2 @g‐C 3 N 4 heterojunction, 9.16 times of Pt NPs/g‐C 3 N 4 , and 1041.97 times of Pt NPs/Zr 3+ ‐ZrO 2 sample, and maintained a good photocatalytic hydrogen generation performance even after five photocatalytic hydrogen evolution cycles. Turnover number (TON) and turnover frequency (TOF) were approximately 105.19 and 35.06 h −1 , respectively. Finally, a plausible S‐scheme charge transfer mechanism of Pt SA/Zr 3+ ‐ZrO 2 @g‐C 3 N 4 heterojunction was suggested for hydrogen generation from seawater splitting.