Near infrared photothermoelectric effect in transparent AZO/ITO/Ag/ITO thin films

A new concept of oxide-metal-oxide structures that combine photothermoelectric effect with high reflectance (similar to 80%) at wavelengths in the infrared (> 1100 nm) and high transmittance in the visible range is reported here. This was observed in optimized ITO/Ag/ITO structure, 20 nm of Silver (Ag) and 40 nm of Indium Tin Oxide (ITO), deposited on Aluminum doped Zinc Oxide (AZO) thin film. These layers show high energy saving efficiency by keeping the temperature constant inside a glazed compartment under solar radiation, but additionally they also show a photothermoelectric effect. Under uniform heating of the sample a thermoelectric effect is observed (S = 40 mV/K), but when irradiated, a potential proportional to the intensity of the radiation is also observed. Therefore, in addition to thermal control in windows, these low emission coatings can be applied as transparent photothermoelectric devices.

Automated summary

A new concept of oxide-metal-oxide structures that combine photothermoelectric effect with high reflectance in the infrared and high transmittance in the visible range is presented in this study. These structures, such as the optimized ITO/Ag/ITO structure, not only show energy saving efficiency by maintaining constant temperature under solar radiation, but also exhibit a photothermoelectric effect. In addition to thermal control in windows, these low emission coatings can be utilized as transparent photothermoelectric devices.