Ga2O3–Cu2O: synthesis, characterisation and antibacterial properties

Abstract

This paper reports on a Ga₂O₃–Cu₂O composite thin film that allows the destruction of both Gram negative and Gram positive bacteria via a dual mechanism involving Ga³⁺ ions that disrupt Fe³⁺ metabolism pathways in bacteria as well as through the reactive oxygen species generated by possible Fenton type reactions that are mediated by Cu¹⁺ ions. This dual mechanism allowed the highly transparent composite thin film to destroy both E. coli and S. aureus to below detection limits in 24 hours and limits the build up of bacterial resistance. The composite film was amorphous and the nature of the Ga and Cu species was extensively analysed on the surface and the bulk using X-ray photoelectron spectroscopy and synchrotron radiation involving linear combination analysis (LCA) and the X-ray absorption near edge structure.