Exploration of Memorial Effect in NiO/MnxOy Piezo Catalysts for Antibacterial Application

This study explores “memorial effect” in NiO/MnxOy piezocatalysts, a phenomenon in which catalytic activity against pathogens persists even after mechanical force is discontinued. The primary objective was to assess this effect’s efficacy in eradicating MDR strains of Staphylococcus aureus and Stenotrophomonas maltophilia from water. We prepared NiO/MnxOy nanocomposites and exposed bacterial suspensions to ultrasonic and gentle shaking treatments. Results demonstrated that the M1–M6 piezocatalysts successfully eradicated S. aureus and S. maltophilia colonies within 24–48 h after cessation of mechanical force, achieving significant reductions compared to controls. Notably, M6 exhibited enhanced antibacterial efficacy, particularly against MDR S. aureus and Escherichia coli, suggesting a potential pathway for water treatment technologies targeting resistant pathogens. These findings underscore the memorial effect’s promising application in developing sustainable, non-chemical water purification methods.