Thermal resistant efficiency of Nb-doped TiO2 thin film based glass window

Abstract

The proportional relationship between the infrared (IR) transmittance of a transparent material and its IR-induced heat transfer can be explained via a simple model. The agreement between theory and the experimental work was examined by measuring the temperature rising inside a heat-insulated box with glass windows under IR irradiation, where the material of the glass windows was modified from corning glass (CG) to 9 at% Nb-doped TiO2 (TNO) fabricated by sputtering deposition. The fabricated TNO thin film was mostly transparent in visible region and had low transparency in IR region, which produced the self- cooling effect inside the insulated box. In comparison to the window glass made by CG, the temperature increase inside the box would be 24% less if the window was made by CG coated by TNO (TNO on CG). This suggests a potential application for the manufacture of products which are effective in energy-cut cooling. The energy-cut was found to decline proportionally to the decrease of the glass window area.