Hydrothermal Synthesis g‑C₃N₄/Nano-InVO₄ Nanocomposites and Enhanced Photocatalytic Activity for Hydrogen Production under Visible Light Irradiation

We synthesized g-C₃N₄/nano-InVO₄ heterojunction-type photocatalyts by in situ growth of InVO₄ nanoparticles onto the surface of g-C₃N₄ sheets via a hydrothermal process. The results of SEM and TEM showed that the obtained InVO₄ nanoparticles 20 nm in size dispersed uniformly on the surface of g-C₃N₄ sheets, which revealed that g-C₃N₄ sheets was probably a promising support for in situ growth of nanosize materials. The achieved intimate interface promoted the charge transfer and inhibited the recombination rate of photogenerated electron–hole pairs, which significantly improved the photocatalytic activity. A possible growth process of g-C₃N₄/nano-InVO₄ nanocomposites was proposed based on different mass fraction of g-C₃N₄ content. The obtained g-C₃N₄/nano-InVO₄ nanocomposites could achieve effective separation of charge-hole pairs and stronger reducing power, which caused enhanced H₂ evolution from water-splitting compared with bare g-C₃N₄ sheets and g-C₃N₄/micro-InVO₄ composites, respectively. As a result, the g-C₃N₄/nano-InVO₄ nanocomposite with a mass ratio of 80:20 possessed the maximum photocatalytic activity for hydrogen production under visible-light irradiation