Constructing novel NaLiTi3O7/g-C3N4 Z-scheme photocatalysts to facilitate the separation of charge carriers and study the hydrogen production performance.

To utilize the UV and visible lights and to improve the separation of photoinduced carriers, a composite composed of NaLiTi3O7 and graphite-carbon nitride (g-C3N4) was constructed. The morphology and microscopic structural details of NaLiTi3O7/g-C3N4 photocatalyst were characterized using XRD, SEM, TEM, XPS, FT-IR, UV-DRS, and TGA techniques. XRD and SEM results showed that well-crystalline NaLiTi3O7 nanoparticles were well dispersed on the surface of g-C3N4 sheets and that the introduction of g-C3N4 effectively alleviated the aggregation of NaLiTi3O7 nanoparticles. UV-DRS results further suggested that the light absorption edge of the NaLiTi3O7/g-C3N4 composite had a significant redshift. Due to these advantages, NaLiTi3O7/g-C3N4 composites exhibited good photocatalytic performance. The hydrogen production performance of all NaLiTi3O7/g-C3N4 samples was much better than that of pure g-C3N4 and NaLiTi3O7 under solar irradiation, and the best NaLiTi3O7/g-C3N4 composite produced 18 times more hydrogen than pure NaLiTi3O7 and 4 times more hydrogen than pure g-C3N4. Compared with pure NaLiTi3O7 or g-C3N4 phases, coupling NaLiTi3O7 with g-C3N4 significantly improved the photocatalytic performance due to the formation of the heterojunction interface between them, which was favorable for the effective separation of the photogenerated electron and hole in a wide light absorption range. [ABSTRACT FROM AUTHOR]