Boosting visible light photocatalytic performance of g-C3N4 nanosheets by combining with LaFeO3 nanoparticles

Highlights: • A Z-scheme LaFeO₃/g-C₃N₄ hybrid was constructed by in-situ growth strategy. • LaFeO₃/g-C₃N₄ exhibited greatly boosted visible light photocatalytic activity. • Holes and superoxide radicals were responsible for methyl orange degradation. • A reasonable Z-scheme was responsible for the augmented photocatalytic activity. - Abstract: A binary direct Z-scheme LaFeO₃/g-C₃N₄ nanohybrid photocatalyst composed of LaFeO₃ nanoparticles and g-C₃N₄ nanosheets was facilely obtained by in-situ growth strategy and employed for the photocatalytic degradation of methyl orange (MO) in aqueous solution under visible light irradiation (λ > 420 nm). As expected, in comparison with pure g-C₃N₄, all of the LaFeO₃/g-C₃N₄ hybrids exhibited the enhanced photocatalytic performance. Noticeably, the LaFeO₃(2.0 wt%)/g-C₃N₄ composite illustrated the highest apparent photodegradation rate constant, which was nearly 17.4 and 4.1 times larger than those of pure LaFeO₃ and g-C₃N₄, respectively. Such a greatly augmented catalytic activity was mainly ascribed to the efficient separation of the photogenerated charge carriers through a Z-scheme system composed of g-C₃N₄ and LaFeO₃, leading to suppressing the photogenerated electrons and holes recombination in both g-C₃N₄ and LaFeO₃ and boosting the photocatalytic efficiency. Furthermore, a probable degradation mechanism was also proposed based on active species trapping experiments, photoluminescence spectroscopy and energy band structures.