Novel Z-scheme 2D/2D Bi4O5Br2/BiOCl heterojunction with enhanced photocatalytic activity for RhB degradation

BACKGROUND With the rapid development of industry and commerce, organic pollutants such as RhB are detrimental to human health and living environment. As a promising technology for treating the organic pollutants in wastewater, photocatalysis technology has received worldwide attention. For practical application, a novel photocatalyst with superior photocatalytic activity should be developed. RESULTS A novel Bi4O5Br2/BiOCl (BC2) heterojunction photocatalyst with 2D/2D structure was fabricated via a facile one-pot solvothermal method. Compared with pure Bi4O5Br2 and BiOCl, the BC2 heterojunction exhibited enhanced photocatalytic performance which reached 91% photodegradation efficiency for RhB under 120 min irradiation of simulated solar-light at pH 7. And 99% RhB was degraded by BC2 under 60 min irradiation at pH 6. CONCLUSION According to experimental and characterization analytical results, the enhanced photocatalytic activity of Bi4O5Br2/BiOCl (BC2) heterojunction could be attributed to the following four points: (i) The BC2 heterojunction with excellent visible light response could effectively utilize the simulated solar-light. (ii) The more negative surface electronegativity of BC2 favored the adsorption of RhB during the photodegradation process. (iii) The 2D/2D BC2 heterojunction had large interface region and internal electric field, thus it displayed superior carriers transfer capability and enhanced charge separation efficiency. (iv) The carriers transfer mechanism of Z-scheme could hinder the recombination of photoinduced charge carriers and endow this photocatalyst with enough redox capacity to degrade RhB. Moreover, slightly acidic condition (pH 6) could promote degradation of RhB, due to the enhanced adsorption capacity of BC2 heterojunction. (c) 2022 Society of Chemical Industry (SCI).