WS₂ and C‐TiO₂ Nanorods Acting as Effective Charge Separators on g‐C₃N₄ to Boost Visible‐Light Activated Hydrogen Production from Seawater

Semiconductor photocatalysis is regarded as an ideal method for use in solving the energy shortage and environmental issues by converting solar energy to chemical energy. Herein, we have designed a facile synthetic methodology to obtain a ternary co-modified g-C₃ N₄ composite via WS₂ and carbon-doped TiO₂ (C-TiO₂ ) nanorods with highly efficient photocatalytic activity for hydrogen production from deionized (DI) water and a natural seawater system under visible-light illumination. This composite exhibits enhanced photocatalytic activity compared to the pristine g-C₃ N₄ , WS₂ , C-TiO₂ nanorods, and the reference-modified g-C₃ N₄ composite with individual WS₂ or C-TiO₂ nanorods. Co-modified g-C₃ N₄ composite shows a great photostability in both DI water and seawater. Under λ=420 nm monochromatic light illumination, the apparent quantum efficiency of the co-modified g-C₃ N₄ composite in seawater solution is 13.08 %, which is higher than pure g-C₃ N₄ (5.06 %). WS₂ , TiO₂ , and g-C₃ N₄ constitute a ternary heterojunction boosting the fast separation of photoinduced electron-hole pairs, which plays a crucial role in enhancing photocatalytic activity. Therefore, the WS₂ and C-TiO₂ nanorod co-modified g-C₃ N₄ composite with high photocatalytic performance provides a promising candidate for rationally utilizing the seawater resource to produce clean chemical energy.