Study on the electrical and thermal conductivity of ordered mesoporous TiO₂ thin film incorporated with Pt nanoparticles

Ordered mesoporous TiO₂ films with incorporated Pt nanoparticles were prepared using titanium tetraisopropoxide, hexachloroplatinic acid hexahydrate, and Pluronic P-123 as a titania precursor, a Pt precursor, and a structure-directing agent, respectively. Pt nanoparticles were introduced to enhance the electrical properties of the mesoporous films, which have excellent thermal insulation properties. We confirmed that the synthesized composite films with Pt nanoparticles had an ordered pore structure with anatase phase TiO ₂ by both small-angle and wide-angle Xray diffraction analyses. Although the porosity of the composite film decreased from 37.6 to 29.3% when Pt nanoparticles were included, the conductivity ratio (σ=κ.) of the film increased greatly, up to approximately 1370 KV^v-2, due to the greater increase in electrical conductivity than thermal conductivity. Based on our results, we conclude that by incorporating Pt nanoparticles into ordered mesoporous TiO₂ film, the thermoelectric properties of the mesoporous films can be improved.