Tailor the antibacterial efficiency of copper alloys by oxidation: when to and when not to

Abstract Copper and its relevant species, such as oxides many alloys, have been recognised potential antibacterial surfaces. Despite the relatively low efficacy of cuprous oxide (Cu 2 O) compared to pure copper, it is still worth consideration in some scenarios. Taking copper-nickel co-sputtered thin films with two copper contents (55 92 at.%) examples, this work investigated oxidation altering behaviour alloy By heat treatment at 200–250 °C for 20–24 h, a layer mainly composed Cu O was successfully fabricated on top Cu-Ni alloys. Antibacterial efficiency against Escherichia coli 1 h obtained by droplet method further compared. The coupons at.% became less effective after oxidation: reduction rate declines from 97.0 74.3%; whereas 55 showed large increase oxidation, rising 15.0 66.8%. experiments described herein reveal promising concept enhancing surfaces applications. Graphical abstract