Point-of-use water treatment: energy-autonomous synergistic solar photothermal-piezocatalysis on MXene/Bi2WO6 membranes for distributed removal of sulfonamide antibiotics.

This work presents an energy-autonomous system for antibiotic removal in distributed water treatment using a MXene/Bi2WO6 membrane that synergistically harnesses solar and hydrodynamic energy. During in-pipe flow under solar irradiation, the membrane achieved efficient removal of sulfamethoxazole (97.9 %). The efficiency surpasses the additive contributions of standalone photocatalysis (PC) and piezoelectric catalysis (PZC) (79.4 %), confirming significant PC-PZC synergy. Mechanistic studies reveal: (1) The piezoelectric field mitigates thermally induced charge recombination, while pyroelectric effects and thermal lattice expansion supplement piezoelectric generation; (2) Periodic band structure modulation and electron polarization likely enhance the degradation process; and (3) In situ electron magnetic resonance verified augmented generation of active multi-species. Crucially, the technology eliminates phytotoxicity risks, reduces antibiotic resistance genes, maintains efficacy across diverse water matrices, and exhibits robust long-term stability. The treated effluent meets reclaimed irrigation water standards, underscoring its positive environmental implications. This work advances novel synergistic catalyst design and offers a unique in-pipe treatment strategy aligned with UN Sustainable Development Goals.