Mesoporous titania (TiO2) thin films have been considered for energy storage applications such as accumulators and electrochemical capacitors. They are also used as electrodes in dye-sensitized solar cells and as high proton conductivity porous exchange membranes in solid oxide fuel cells. Moreover, Choi et al. identified mesoporous TiO2 thin films as promising thermal insulating materials for infrared sensors. Finally, other applications include (i) highly specific chemical sensors and membranes, (ii) photocatalyst for water and air purification, and (iii) optical coatings, emissive displays, and optoelectronics.
Knowledge of thermal properties of mesoporous titania thin films is essential to their practical implementation into devices. The present study aims to (i) measure the effective cross-plane thermal conductivity of mesoporous TiO2 thin films with various nanoscale architectures and (ii) investigate the effects of temperature, presence of pores, and crystallinity of the TiO2 matrix over the temperature range from 30 to 320 K.
The cross-plane thermal conductivity of highly-ordered amorphous and crystalline templated mesoporous titania thin films was measured by the 3ω method from 30 to 320K.
J. Fang, C. Kang, Y. Huang, S.H. Tolbert, and L. Pilon, 2012. Thermal Conductivity of Ordered Mesoporous Nanocrystalline Silicon Thin Films Made from Magnesium Reduction of Polymer-Templated Silica. Journal of Physical Chemistry C, Vol. 116, No. 23, pp. 12926–12933. doi: 10.1021/jp302531d pdf
J. Fang, C. Reitz, T. Brezesinski , E. J. Nemanick, C.B. Kang, S.H. Tolbert, and L. Pilon, 2011. Thermal Conductivity of Amorphous and Crystalline Mesoporous Titania Thin Films from 30 to 320 K. The Journal of Physical Chemistry C, Vol. 115, No. 30, pp 14606–14614. doi:10.1021/jp203400t pdf
T. Coquil, C. Reitz, T. Brezesinski , E. J. Nemanick, S.H. Tolbert, and L. Pilon, 2010. Thermal Conductivity of Mesoporous Titania Films Made From Nanocrystalline Building Blocks and Sol-Gel Reagents, The Journal of Physical Chemistry C, Vol. 114, no. 29, pp 12451–12458. doi:10.1021/jp103251t pdf
T. Coquil, E. Richman, N. Hutchinson, S. Tolbert, and L. Pilon, 2009. Thermal Conductivity of Cubic and Hexagonal Mesoporous Silica Thin Films, Journal of Applied Physics, Vol. 106, no.3, 034910. Selected to appear in Virtual Journal of Nanoscale Science & Technology, Vol. 20, no.8, August 24, 2009. doi:10.1063/1.3182826 pdf