Enhanced built-in electric field by asymmetric Mo-doped BiVO4 for photoelectrocatalytic detoxification of ofloxacin in hyposaline wastewater
Photoelectrocatalytic (PEC) detoxification of ofloxacin in hyposaline wastewater is hindered by weak built-in electric fields (IEF) and rapid charge recombination. Here, we report a crystal dipole engineering strategy using high-valence Mo-doped BiVO4 to enhance IEF and PEC activity. Mo incorporation breaks lattice symmetry, increasing the crystal dipole moment and amplifying IEF to 2.05 times that of pristine BiVO4. This promotes directional carrier migration, improving electron-hole separation efficiency. The optimized 4% Mo-BiVO4 photoanode achieves 96.5% ofloxacin degradation within 60 minutes and maintains 91.9% degradation efficiency in natural lake water containing saline and organic interferents, demonstrating exceptional anti-interference capability. This work provides a strategy for boosting photocatalytic performance through unit-cell dipole engineering, aiming to enhance sustainability in wastewater treatment.