In-situ growth of metal phosphide-black phosphorus heterojunction for highly selective and efficient photocatalytic carbon dioxide conversion

Two-dimensional black phosphorus-based nanomaterials with distinct properties have emerged as fascinating semiconductor photocatalysts. In this work, metal phosphide (M-P: Co2P, Ni-P and Cu-P) in-situ growth on black phosphorus (BP) nanosheets is developed for photocatalytic carbon dioxide conversion. The M-P/BP heterojunction, especially Co2P/BP materials, show largely improved carbon dioxide capturing ability and charge separation efficiency. More importantly, the catalytic active Co in Co2P/BP can activate the adsorbed CO2 molecules and further boost the electron-hole separation process, which improves the photocatalytic activity for carbon dioxide reduction. The obtained Co2P/BP presented a photocatalytic CO production rate of 255.1 μmol/g∙h, which was almost two times higher than that of bulk BP (141.8 μmol/g∙h). This work shows that M-P/BP materials have high potential in photocatalytic CO2 reduction due to their high stability and performance.