Cu/Ag bimetallic nanoparticles produced by cylindrical post-magnetron gas aggregation source - A novel galvanic corrosion-based antibacterial material

A novel strategy to produce bi-metallic heterogeneous Cu/Ag nanoparticles using the gas aggregation source based on cylindrical post-magnetron with segmental Cu/Ag targets is introduced and investigated. It is shown that the production rate of nanoparticles depends not only on the magnetron current and aggregation pressure but also on the ratio of the Cu and Ag in the segmental target. Enhanced production of nanoparticles for larger Cu part in the segmental target has been observed. Furthermore, it is demonstrated that various types of Cu/Ag nanoparticles may be produced including dumbbell-like or onion-like ones with well-separated Cu and Ag domains. Finally, it has been for the first time confirmed that the gas-phase synthesized heterogeneous Cu/Ag nanoparticles are prone to extensive galvanic corrosion. This effect promotes the antibacterial efficiency of Cu/ Ag nanoparticles compared to mono-metallic Cu ones, making such nanoparticles highly interesting for medical applications.