Fig. 1: Working principle of the resonance-vibration-driven (RV)-disinfection system for air-transmitted microbes.

a Schematics of the RV-disinfection system in an air duct. It consists of a triboelectric nanogenerator (TENG), a power management system with rectifiers, and a three-electrode disinfection filter for air-transmitted microbial disinfection. The resonance frequency of the TENG was designed to be the same as the vibration frequency of the ventilators found in buildings to achieve a significant amplitude for greater power output. b Illustrations of the disinfection filter in the RV-disinfection system. It consists of a macro-mesh negative electrode and integrated positive/ground electrodes. In Step 1, microbes (bacteria and viruses) in the air come into contact with the surface of the macro-mesh electrode and are charged negatively when flowing through the negative electrode. In Step 2, the charged microbes then flow between the positive and ground electrodes and are trapped on the positive electrode surface by electrostatic attraction. In Step 3, when the microbes approach the positive electrode, whose surface is modified by nanowires, they will enter the vicinity of the nanowire tip structure where an enhanced localized electric field exists and become inactivated by electroporation. c Schematics of the copper-phosphide-nanowire-modified copper plate (Cu₃PNW-Cu) electrode synthesis: copper hydroxide nanowire (Cu(OH)₂NW) synthesis on the copper surface by electrochemical oxidation and Cu₃PNW synthesis by phosphidation. d, e Scanning electron microscope (SEM) and optical images showing the Cu(OH)₂NW-modified copper plate (Cu(OH)₂NW-Cu) electrode (d) and the Cu₃PNW-Cu electrode (e). Scale bars for inset figures in (d) and (e) are 3 cm.