Preparation method and application of broadband spectral response composite material based on black phosphorus nanosheet

The invention provides a composite photocatalytic material based on black phosphorus nanosheets, and discloses a preparation method and photo-thermal synergistic effect application of a wide spectral response composite photocatalytic material based on black phosphorus nanosheets. The preparation method comprises the following steps: firstly, stripping blocky black phosphorus powder into black phosphorus nanosheets through liquid nitrogen freezing, ice bath and ultrasonic treatment; a solvothermal method is adopted, a nickel salt solution and the prepared CdLa2S4 nanomaterial are mixed in black phosphorus nanosheet dispersion liquid for reaction, the CdLa2S4/BP-coated Ni2P/Ni composite photocatalytic material is prepared, Ni2P and Ni are obtained through in-situ growth, and coexistence of a heterojunction and a cocatalyst is achieved. The obtained nano composite material is high in purity and good in crystallinity and has relatively strong absorption characteristics in visible light and near-infrared regions,