Chemical Engineering Journal

Photothermal–photocatalytic system, Solar steam generation, Photocatalytic H₂ production, Seawater splitting

Photocatalytic water splitting enables direct solar-to‑hydrogen (H2) conversion. However, challenges remain, such as its reliance on pure water and poor utilization of both thermal energy and photons. Herein, we design a photothermal-photocatalytic system by integrating nitrogen-vacancy engineered g- C₃N₄ (NvCN) with carbonized wood (CW), enabling the simultaneous generation of freshwater and H₂ from seawater. In this system, seawater is continuously delivered via capillary wicking through the CW substrate to the carbonized surface, where it is vaporized by the photothermal effect and subsequently split into H₂ by NvCN through photocatalysis, while the unreacted vapor is condensed to produce fresh water. This unique system exhibits a water evaporation rate of 1.14 kg m−2 h−1 and a high H2 production rate of 23.01 mmol m−2 h−1, which is nearly 2 times higher than that of the conventional powder-suspension system (11.72 mmol m−2 h−1), while maintaining stable operation in various natural water sources, such as seawater, spring water. The improved photocatalytic performance is mainly attributed to the synergistic optimization of reaction thermodynamics, energy transfer, and mass transfer. Furthermore, optimizing the composition and structure of NvCN–CW facilitates efficient allocation of solar energy applied between photothermal evaporation and photocatalytic H2 evolution.

Risheng Duan

Ning Qin,Pei Zhao

Ikram Ullah,Waqar Ahmad Qureshi

Journal paper

175742

535

175742

No

2026-04

EI、SCI