Study of the effect of a silver nanoparticle seeding layer on the crystallisation temperature, photoinduced hydrophylic and catalytic properties of TiO2 thin films deposited on glass by magnetron sputtering

The optimization of the photocatalytic activity and hydrophilic conversion of TiO2 is an active research area in the field of self-cleaning materials and energy storage/conversion. One major focus is the crystalline phase of TiO2, known to be the most efficient of the anatase structures. Another issue is the decoration of TiO2 with noble metals, which act as charge carrier traps for electrons. The latter hinders or reduces the electron–hole recombination rate and often leads to a more efficient photocatalytic activity. s paper, we describe how an interlayer consisting of 3–4 nm silver nanoparticles (Ag-NPs) promotes TiO2 anatase crystallisation and has a positive effect on the photoinduced catalytic and hydrophylic properties of TiO2 thin films. Ag-NPs and TiO2 were deposited by magnetron sputtering in the same reactor in a two-step process: a) condensation of Ag-NPs produced in the gas phase thanks to a high-pressure discharge, and b) conventional TiO2 magnetron deposition in oxide mode. Four temperatures from RT to 288 °C were investigated and film thickness was 80 nm. le size and film structure were determined by TEM, HRTEM and XRD. Photocatalytic activities of the samples were tracked by the evaluation of the surface hydrophilicity after UV illumination and 24 hours post-illumination, and by UV-induced palmitic acid degradation.