Piezoelectric-enhanced rapid degradation of sulfamethoxazole using the Co3O4/Bi0.5Na0.5TiO3/Peroxymonosulfate process

• Piezo and PMS coupled-catalytic system was constructed. • The Co 3 O 4 @BNT/US/PMS showed ultrafast degradation ability for SMX in 2 min. • Piezoelectric catalysis-coupled PMS activation produces more active species. • The Co 3 O 4 @BNT/US/PMS showed excellent rate constant for SMX about 1.4992 min −1 . The rapid degradation of pollutants is crucial for facilitating large-scale industrial wastewater treatment; however, most current methods exhibit slow degradation rates for sulfamethoxazole (SMX). Piezoelectric catalysis coupled with PMS-based advanced oxidation process (AOPs) shows great potential for efficiently degrading SMX. To address these issues, we developed a piezoelectric-coupled AOP system by fabricating Co 3 O 4 /Na 0.5 Bi 0.5 TiO 3 (Co 3 O 4 /BNT) catalysts. The Co 3 O 4 /BNT/PMS/US system demonstrated remarkable catalytic efficiency, achieving 96 % SMX degradation (20 mg/L) within 2 min. The process follows pseudo-first-order kinetics, with a rate constant of 1.49 min -1 , 253 times higher than using ultrasound alone and 41 times higher than using AOPs alone. The introduction of Co 3 O 4 enhances charge separation and transfer within the built-in electric field of BNT, which synergistically strengthens its piezoelectricity and significantly boosts PMS activation through rapid charge dynamics, thereby achieving high-performance SMX degradation. In addition, Co 3 O 4 doping promotes the generation of SO 4 •- and 1 O 2 radicals, which drive the degradation of SMX.