One-pot preparation of double S-scheme Bi2S3/MoO3/C3N4 heterojunctions with enhanced photocatalytic activity originated from the effective charge pairs partition and migration

In this article, double S-scheme Bi2S3/MoO3/C3N4 heterojunctions with excellent photocatalytic performance were fabricated via a facile one-pot solid-state reaction. The structural and morphological analysis of the as-prepared heterojunctions was implemented to understand the crystal structure and surface properties. The results of photocatalytic experiments exhibit that Bi2S3/MoO3/C3N4 heterojunctions prepared by 11.5 g thiourea, 0.1333 g ammonium molybdate tetrahydrate and 0.02 g bismuth(III) citrate display the highest activity under solar light irradiation, the activity of which is seven times of that of C3N4, and nearly three times of that of MoO3/C3N4. The ameliorated performance originates from the construction of double S-scheme heterojunctions which possesses the effective charge pairs partition and migration. The cycling experiments display that Bi2S3/MoO3/C3N4 heterojunctions exhibit remarkable stability. In the light of the radical trapping experiments, nitroblue tetrazolium (NBT) experiments, electron spin resonance (ESR), and the match of energy band, double S-scheme mechanism was proposed. This work also provided a new facile solid-state reaction method to synthesize double S-scheme heterojunctions with high performance for efficient abatement of pollutants.