Preparation and properties of Ag-coated activated carbon nanocomposites for indoor air quality control

Activated carbon (AC) has been widely used in indoor air quality (IAQ) control for removal of hazardous volatile organic compounds (VOCs). A detrimental effect of this adsorption technology is that bacteria multiplied on AC may deteriorate IAQ. In this paper, antibacterial AC nanocomposites with well-dispersed silver nanoparticles (Ag/ACs) were prepared by the attachment of Ag+ on the functionalized AC surface via ion–dipole interactions and the subsequent in-situ reduction of Ag+. The surfaces and microporous structures of the obtained Ag/ACs were analyzed by means of scan electron microscope (SEM) and pore size surface area analysis. Antibacterial tests were performed using Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) as model bacteria. Antibacterial activity against airborne bacteria and toluene adsorption capacity of AC nanocomposites were further evaluated. It was found that the introduction of Ag nanoparticles significantly improves antibacterial effect of AC but slightly reduces toluene adsorption ability. Ag/ACs can efficiently kill bacteria within 100 min without decreasing adsorption ability toward toluene.