Study on the Electrical and Thermal Conductivity of Ordered Mesoporous TiO₂ Thin Film Incorporated with Pt Nanoparticles

Abstract

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 TiO2 by both small-angle and wide-angle X-ray 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 K 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.

Synchronous achievement of ultra-wideband microwave absorption and high thermal conduction in spongy TiO2-based magnetic composites via constructing magnetic/dielectric double loss and phonon/electron co-transmission

“…11b). 2,11–20,65–70 Moreover, the loading amount of 30% is lower than those of most other fillers (45–100%). 2,11–20,69…”

“…11,12 Its thermal conduction can be boosted by controlling its loading amount, pH value, size, shape, viscosity, and dispersion, or by incorporating TiO 2 with other materials (Cu, Pt, SiO 2 , Al 2 O 3 , CuO, Er 2 O 3 , ZrO 2 , Cu 2 Se, SiC, and C). 11–20 Nevertheless, the current TiO 2 and its composites utilized as thermal-conductive fillers have high loading (52–100%) and low TC (0.122–2.78 W (m K) −1 ) and thus are unsuitable for practical application. 13–20…”

“…11–20 Nevertheless, the current TiO 2 and its composites utilized as thermal-conductive fillers have high loading (52–100%) and low TC (0.122–2.78 W (m K) −1 ) and thus are unsuitable for practical application. 13–20…”

Preparation of mesoporous nitrogen-doped titania comprising large crystallites with low thermal conductivity

“…Therefore, it is necessary to increase the ZT value of TiO 2 by doping it with different elements to increase σ and by reducing κ toward its utilization as a thermoelectric material. The improved thermoelectric performances of sintered N-doped TiO 2 nanoparticles 13,14 and Nb-doped 15 or Pt-loaded 16 mesoporous TiO 2 thin films have been reported.…”

“…Therefore, the pore arrangement of the hexagonal structure can further reduce κ , and mesoporous TiO 2 exhibiting a regular pore arrangement can effectively reduce κ . However, the reduction of the κ of mesoporous TiO 2 exhibiting a regular pore arrangement was only measured in thin films, 15,16,30,31 and additional findings employing bulk samples, such as pellets, are required for further studies and applications. Furthermore, the temperature dependence of κ above room temperature has not been investigated.…”