Electronically asymmetric Ru-O-Bi sites enable complementary peroxymonosulfate activation for integrated...

The co-occurrence of antibiotics, antibiotic-resistant bacteria (ARB), and antibiotic resistance genes (ARGs) in wastewater drives the environmental spread of antimicrobial resistance. While peroxymonosulfate (PMS) oxidation can generate diverse reactive species, coordinating the production of both radical and non-radical oxidants remains challenging due to the uniform electronic properties of conventional catalytic sites. To address this, we engineered an electronically asymmetric Ru-O-Bi dual-site catalyst by introducing atomically dispersed ruthenium into Bi₄TaO₈Cl. Spectroscopic characterization and density functional theory calculations indicate that Ru incorporation generates electronically differentiated Bi- and Ru-associated environments that preferentially favor reductive and oxidative PMS activation, respectively. Consistent with this site-preferential model, EPR and molecular-probe measurements demonstrated the concurrent generation of SO₄^•-, •OH, and ¹O₂. In batch experiments, the resulting RBTOC/PMS process achieved complete ARB inactivation within 6 min, a 6.42-log reduction in tetA abundance within 10 min, and over 90% removal of tetracycline (TC) within 5 min. The apparent rate constants for tetA and TC degradation reached 2.98 and 1.60 min^-1, respectively. Furthermore, a 360-h continuous-flow reactor treating real secondary effluent maintained 99.99% bacterial inactivation, a 4.9-log reduction in tetA, and over 90% removal of TC. These findings show that electronic differentiation within the Ru-O-Bi environment supports complementary radical and non-radical PMS activation and enables effective treatment of representative antibiotic-, ARB-, and ARG-related contaminants, providing a long-duration continuous-flow proof of concept for multi-target wastewater treatment.