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

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.