Comparison of Photocatalytic Biocidal Activity of TiO2, ZnO and Au/ZnO on Escherichia coli and on Aspergillus niger under Light Intensity Close to Real-Life Conditions

Microbial contamination of the surface building materials and subsequent release microbial particles into air can significantly affect indoor quality. Avoiding development or, at least, reducing quantity microorganisms growing on is a key point to reduce health risks for occupiers. In that context, antimicrobial activity TiO2, ZnO Au/ZnO was assessed by measuring log reductions Escherichia coli Aspergillus niger populations both in dark under light intensity close real-life conditions. The bactericidal activities (≥2.3 reduction) tested products were stronger than their fungicidal (≤1.4 after 2 h contact. Different parameters including concentration photocatalyst, (dark vs. 5 W/m2 UV-A), duration contact between photocatalyst cells spores investigated. Results this study confirmed AuZnO E. brought new insight A. niger. They also greatest efficiency compared TiO2 its increased photocatalytic when decorated with Au, leading highest detected (4 1.4 niger, respectively). enhanced nanoparticles different products.