Development of titania coatings on glass foams

TiO2 coatings on glass foam substrates were produced by electrophoretic deposition (EPD) and sol–gel method with the aim to impart surface functional properties to glass foam such as antibacterial and photocatalytic effects. Starting with charged TiO2 nanoparticles (21 nm) suspended in acetylacetone, EPD was shown to be a useful method to obtain TiO2 coating on the glass foam substrates placed close to the deposition electrodes in the EPD cell. Best results were obtained by applying 25 V for 4 min and a subsequent thermal treatment (450 °C for 1 h). In the second approach, multilayer sol–gel TiO2 coatings on glass foam were fabricated, which were heat-treated at 450 °C for 1 h to obtain pure anatase structure. Both techniques led to partially microcracked coatings which were however well adhered to the glass foam substrate (qualitatively assessed). The presence of microcracks was not considered to be a disadvantage as they increase the surface area of the coating, which is required to maximise the interaction of the titania layers with the environment for their antibacterial and photocatalytic function.