Abstract: The coronavirus disease 2019 (COVID-19) caused a large number of deaths and serious economic losses. Safety precautions and effective measures are urgently demanded to control the virus spread in public places. Owing to the longevity of the viruses in the aerosols and surfaces, sustained nanomaterials with efficient antiviral abilities during both daytime and night appear to be a promising way to control virus spread. Here, AgCu nanocomposites, which are outstanding antibacterial and antiviral elements, including Ag₂Cu₂O₃ and AgCuO₂, have been successfully prepared via a simple co-precipitation method for inactivation of model Qbeta (Qβ) bacteriophage. Notably, Ag₂Cu₂O₃ has uniform nanorods morphology with a width of 50-100 nm and a length of 200-500 nm, regular elemental states of Cu²⁺ and Ag⁺, and good visible light response. Instead, AgCuO₂ has more complex elemental states of Cu²⁺, Ag⁺, and Ag³⁺, including morphology with large particles of 500-1000 nm surrounded by small nanorods and nanoplates. Density functional theory (DFT) calculations showed that Ag₂Cu₂O₃ has a lower work function than AgCuO₂, indicating the charges can be better released from the surface. The accumulated surface charge can bind to the virus to inactivate it. As a result, Ag₂Cu₂O₃ shows outstanding antiviral properties with a 6-log reduction (99.9999 %) of Qβ phage after 45 min contact under dark condition, and the activity can be further promoted to 7.5-log inactivation of Qβ phage after the same time contact under visible light irradiation, revealing its potential to sustainably prevent viruses spread in indoor environments.

Key words: Ag₂Cu₂O₃, AgCuO₂, Qβ bacteriophage, Work function