Enhanced photo-Fenton system across wide pH range based on Fe-Bi2WO6: Insight into the regulable microenvironment and ROS generation

Traditional Fenton reaction is limited by strict pH and iron sludge. integrating photo-Fenton enables operation under mild conditions. We report a one-step hydrothermal synthesis of Fe-modified Bi 2 WO 6 (Fe-BWO) to create an efficient photo-Fenton synergistic system for ciprofloxacin (CIP) removal under visible light. The Fe-BWO system achieved 83.7 % CIP degradation in 1 h, surpassing standalone photocatalysis and homogeneous Fenton. The degradation rate was 6 times that of photocatalysis and 1.5 times that of homogeneous Fenton. Crucially, the system exhibited excellent stability, wide pH applicability, and low H 2 O 2 consumption OH, and ·O 2 − were confirmed as major reactive species. Mechanistic studies indicate that the narrowed band gap promotes electron migration, while H 2 O 2 -induced surface microenvironment variation (attributed to Bi (3−x)+ electron redistribution) is vital for molecular oxygen activation. This work offers novel insights into H2O2 activation and the impact of surface microenvironments in photo-Fenton processes.