Z-scheme Bi2O3/Zn3V2O8 inorganic photocatalysts: Enhanced visible light performance, mechanistic understanding, and antimicrobial potential

The activation of persulfate (PS) has gained attention as an effective method to enhance advanced oxidation processes, and its synergy with photocatalysis presents a promising route for pollutant degradation. Persulfates (S2O82- ), known for their strong oxidizing power, generate highly reactive free radicals upon activation, making them particularly effective in degrading persistent organic pollutants. In this study, a novel Bi2O3/Zn3V2O8 heterojunction photocatalyst, synthesized via a simple hydrothermal method with varying Bi2O3 ratios, was employed for the degradation of crystal violet (CV) dye under visible light illumination using S2O82- . The Bi2O3/ Zn3V2O8 (BZV) heterostructures exhibited markedly higher photocatalytic activity for CV degradation than Zn3V2O8 and Bi2O3 alone. In particular, the heterostructure containing 40 % Bi2O3 (40 %-BZV) exhibited the highest activity due to the synergistic interaction between Bi2O3 and Zn3V2O8. Using this photocatalyst, complete degradation of CV was achieved within 30 min, under optimal conditions of initial CV concentration of 10 ppm, catalyst dosage of 250 mg/L, and initial PS concentration of 0.125 mM. Additionally, trapping experiments were conducted to elucidate the reaction mechanisms in the 40 %-BZV/PS/Vis system. These experiments revealed that holes were the primary reactive species driving the CV degradation process. Based on these results, we demonstrated that the Z-scheme was the main heterojunction involved. Furthermore, this system stands out for its reliability, confirmed by the stability of the 40 %-BZV photocatalyst after up to 10 cycles of regeneration. This study provides a comprehensive evaluation of a high-performance heterostructure photocatalyst, utilizing PS as an activator for CV dye degradation under visible light illumination, offering an effective and eco-friendly solution for the degradation of organic pollutants.