Promotional antibacterial performance under dark conditions by silver induced oxygen adsorption and charge transfer

Exposure to airborne pathogens poses substantial health hazards, highlighting the necessity for efficient antimicrobial techniques. However, conventional antimicrobial techniques often fail to provide continuous disinfection . This study proposed a method for developing antimicrobial materials that could function effectively in the dark, focusing on the synthesis of CuAgO x catalysts with abundant oxygen vacancies to inhibit the growth of Escherichia coli and Staphylococcus aureus without light irradiation . Among the catalysts tested, CuAgO x -3 demonstrated superior antibacterial efficacy, achieving over 99.99 % inactivation of both Gram-negative ( E. coli ) and Gram-positive ( S. aureus ) bacteria within 15 min under dark conditions. EPR confirmed that the incorporation of silver ions enhanced the adsorption of oxygen molecules. Density functional theory (DFT) calculations revealed that CuAgO x -3 sample exhibited more active electronic states and stronger oxygen adsorption and activation ability, thereby facilitating the generation of reactive oxygen species . ROS damage bacterial membranes by attacking lipopolysaccharide (LPS) and phosphatidylethanolamine (PE). Intracellular ROS assays and electrophoresis experiments confirmed DNA damage in the bacteria. CuAgO x samples also revealed high antimicrobial efficiency (>98.00 %) against airborne microorganisms under dark conditions, showing potential applicability to inhibit the spread of pathogenic microorganisms . Collectively, these findings expand the knowledge base regarding the antimicrobial efficacy of materials in dark environments. • Oxygen vacancies enhance the antimicrobial activity of CuAgO x -3 under dark conditions. • Ag + doping promotes oxygen molecule adsorption and electron transfer in CuAgO x -3. • . O 2 - and 1 O 2 can react with bacterial membranes by attacking lipopolysaccharide and phosphatidyl ethanolamine. • CuAgO x -3 nanocatalyst demonstrates significant antibacterial activity against airborne microorganisms under dark conditions.