▎ 摘　　要

NOVELTY - Biocidal nanocomposite comprises graphene, a photocatalyst and a biocide comprising metal nanoparticles, where the biocide comprise copper nanoparticles. USE - The biocidal nanocomposite is used in coating composition and a coating substrate, such as masonry walls, wood, ceramics, metals, glass or plastics, and for disinfecting hard surfaces. The antimicrobial efficacy of the biocidal nanocomposite was tested on plastic substrates. The results showed that 99.99% and 100% bacterial reduction of Escherichia coli and Staphylococccus aureus were achieved after 24 hours. ADVANTAGE - The biocidal nanocomposite is cost-effective, has improved biocidal activity and robustness, improved continuous disinfection of hard surfaces, and enhanced disinfecting effect relative to conventional materials and/or formulations comprising photocatalysts. DETAILED DESCRIPTION - INDEPENDENT CLAIMS are included for the following: (1) (1) a method for preparing the biocidal nanocomposite, involving (a) preparing a first mixture comprising a dispersion of graphene, a photocatalyst and a chemical linker for attaching the photocatalyst to graphene, (b) preparing a second mixture comprising metal nanoparticles, where the metal nanoparticles comprise copper nanoparticles, and (c) combining the first mixture and the second mixture to obtain the biocidal nanocomposite; (2) (2) a coating composition comprising the nanocomposite; (3) (3) a coated substrate comprising a coating layer formed from the coating composition; and (4) (4) a coated article comprising the coating layer having a dry film thickness of 1-5 microns.