Unveiling new insights into photocatalytic enhancement of p-n BiVO4-OV/NiMoO4 Heterojunctions through oxygen defect engineering

Abstract

The development of efficient and stable photocatalysts holds vital importance in the fast and effective removal of toxic contaminants from wastewater. In this study, novel 1D/2D BiVO₄-OV/NiMoO₄ hybrid with enriched oxygen vacancies (BiVO₄-OV/NiMoO₄) were successfully synthesized by using one step hydrothermal synthesis route. Utilizing the p-n heterojunction and oxygen vacancies, the optimized BiVO₄-OV/NiMoO₄ composite exhibited exceptional photocatalytic efficiency, achieving a photocatalytic degradation efficiency of 92 % for rhodamine B (RhB) under visible light irradiation within 60 min. The apparent rate constant of value of optimized BiVO₄-OV/NiMoO₄ composite is 0.02864 min⁻¹, exceeding those of BiVO₄ and NiMoO₄ by 4.4 times and 5.5 times, respectively. The photocatalytic mechanism and degradation pathways of RhB were investigated through active species trapping experiment. Remarkably, optimized BiVO₄-OV/NiMoO₄ hybrid demonstrated high stability and recyclability. This study on the development of highly efficient visible-light catalysts through synergistic defect and heterojunction engineering, offering a promising approach for organic pollutant degradation.