Construction of visible-light responsive direct Z-scheme p–n BiOI/LaCoO₃ heterostructure for removal of organic contaminants

Over the past few decades, semiconductor of light-driven photocatalysis has proven to be one of the most promising and effective methods for removing antibiotics from water. Herein, the p–n BiOI/LaCoO₃ heterostructure is designed and fabricated. First, one-dimensional (1D) p-type LaCoO₃ nanoribbons are fabricated by electrospinning. Then the three-dimensional (3D) n-type BiOI nanoflowers are immobilized on 1D p-type LaCoO₃ nanoribbons by using a subsequent solvothermal method. The optimized BiOI/LaCoO₃ heterostructure exhibits excellent performance in removing tetracycline hydrochloride (TCH), with a degradation rate of 98.4% (120 min), which is 3.4 times higher than the LaCoO₃ nanoribbons. Interestingly, under visible-light irradiation, BiOI/LaCoO₃ heterostructures exhibit broad-spectrum applications for different types of organic pollutants. The test results verify that the large specific surface area of the BiOI/LaCoO₃ heterostructure, and the formation of a direct Z-scheme with p–n heterostructure are the main reasons. This study paves the way for constructing high-performance direct Z-scheme p–n heterostructure to achieve photocatalytic water purification.