A photocatalyst made using a combination of titanium dioxide (TiO2) and copper oxide (CuxO) nanoclusters inactivates various variant types of novel coronavirus SARS-CoV-2. In a recent breakthrough, scientists in Nara Medical University, Kanagawa Institute of Industrial Science and Technology, and Tokyo Institute of Technology have developed this antiviral photocatalyst, which has been proven to be effective under both darkness and indoor light.