Construction of p-ZnBi2O4/n-BiOBr Heterojunctions for Efficient Visible-Light Photocatalytic Degradation of Dyes

Abstract

A composite series, (1-x)ZnBi2O4/x-BiOBr, was synthesized using a two-step hydrothermal method. The x = 0.7 composite demonstrated 100 % removal of RhB in 10 minutes (k = 0.2317 min⁻¹) under visible light, ~74 times higher than ZnBi2O4 (k = 0.0031 min⁻¹). For Orange G, x = 0.7 yielded 100 % removal in 30 min with k = 0.1053 min⁻¹, ~14 times greater than ZnBi2O4. The improved activity correlates to high SBET (21.8 m² g⁻¹) and good interfacial charge separation. Band-edge estimates and scavenger tests suggested a type-II‐like band alignment. Moreover, the x=0.7 composite retained ≥81 % of activity over 5 cycles.