Employing cold atmospheric plasma (Ar, He) on Ag thin film and their influences on surface morphology and anti-bacterial activity of silver films for water treatment

摘要

In this work to investigate the effects of using different gases in cold atmospheric plasma (CAP) on surface treatment of silver thin films (100, 120?nm film thickness) He and Ar were employed. Ag was sputtered on glass substrate and X-ray diffraction (XRD) as well as atomic force microscopy (AFM) for structural and morphological studies before and after plasma radiation was carried out. Surface treatment of Ag thin films by CAP increased surface roughness especially with Ar plasma, this rise of surface roughness of Ag thin film leads to make their surface hydrophilic which can be very important for antibacterial activity of Ag films in removal of Escherichia coli ( E. coli ) which was used as target bacterium. Argon plasma radiation was more effective than helium on both surface morphology and anti-bacterial property. XRD results showed that crystalline orientation of [111] peak of silver remains as preferred orientation, but the grain size did not change that much after plasma treatment. The crystalline size was calculated by Debye–Scherrer formula using peak [111] of Ag samples (as the most intense peak of silver).