Composite material for assisting in degrading dye wastewater as well as preparation method and application of composite material

The invention relates to the field of catalytic composite materials, and particularly discloses a composite material for assisting in degrading dye wastewater as well as a preparation method and application of the composite material. According to the invention, hydrotalcite and lanthanum salt are taken as main bodies, and the hydrotalcite and lanthanum salt compound with a p-n heterojunction structure is prepared by using a coprecipitation method. The composite material can assist peroxymonosulfate to oxidize and degrade harmful substances in azo dye wastewater, the degradation efficiency of peroxymonosulfate is improved, and the composite material is stable in catalytic performance, simple and convenient to use and reusable, so that the dye wastewater degradation cost is greatly saved. The problems that in the prior art, due to the fact that a photocatalyst is adopted for assisting persulfate to degrade the dye wastewater, the performance of the catalyst is unstable, the catalytic activity is greatly reduced