The anti-microbial properties of copper have been well established and researched.
Copper has antimicrobial properties, meaning it can kill microorganisms like bacteria and viruses. However, the microorganism has to come in contact with the copper in order for it to be killed. This is referred to as "contact killing."
The scientists found that severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was detectable in aerosols for up to three hours, up to four hours on copper, up to 24 hours on cardboard and up to two to three days on plastic and stainless steel.