Sandwich-like mesoporous graphite-like carbon nitride (Meso-g-C3N4)/WP/Meso-g-C3N4 laminated heterojunctions solar-driven photocatalysts

Three-dimensional mesoporous graphite-like carbon nitride (Meso-g-C3N4/WP/Meso-g-C3N4) laminated heterojunction nanosheets are successfully synthesized by solid-phase in situ reduction combined with high temperature calcination. Meso-g-C3N4/WP/Meso-g-C3N4 has a relatively high specific surface area of 82 m2 g-1, a large pore size of 8-15 nm, and a narrow band gap of ~2.7 eV. The solar-driven photocatalytic reaction hydrogen production rate (~198.1 μmol h-1g-1) for Meso-g-C3N4/WP/Meso-g-C3N4 3D laminated heterojunctions is approximately 10 times higher than that of pristine g-C3N4. This discrepancy can be attributed to the synergistic effect of the 3D interbed heterojunction structure, which favors the spatial separation of photogenerated charge carriers due to its suitable band positions; its nanosheet structure, favoring the charge transfer to surface; and its mesoporous structures, offering more surface active sites and facilitating mass transfer. This novel sandwich-like laminated heterojunction structure offers new insights for the fabrication of other high-performance photocatalysts.