Applied Optics · 1976 · 226 citations · 3 references
Natural SciencesMaterials EngineeringMaterials ScienceEnergy MaterialsOptical MaterialsThin FilmsInfrared Optical MaterialsOptical Thin FilmsSolar CellsSolar Energy SystemsSolar RadiationThin Film Optical PropertiesAbsorber MaterialsEmissivityLight-absorbing LayersRadiative Properties Of MaterialsSolar Energy ConversionThermal ConversionThermal RadiationWindow Insulation
Transparent heat‑mirror films transmit solar radiation while reflecting infrared thermal radiation, offering potential benefits for solar‑thermal conversion, photovoltaic efficiency, and window insulation. The study aims to characterize heat‑mirror performance for solar‑energy collection by defining effective solar absorptivity (αeff) and effective infrared emissivity (∊eff). The authors fabricated TiO₂/Ag/TiO₂ and Sn‑doped In₂O₃ films via rf sputtering and used the defined parameters to evaluate their heat‑mirror properties. The Sn‑doped In₂O₃ films exhibit αeff/∊eff ratios comparable to leading selective absorbers, whereas TiO₂/Ag/TiO₂ films achieve even higher ratios.
Transparent heat-mirror films, which transmit solar radiation but reflect ir thermal radiation, have potentially important applications in solar/thermal/electric conversion, solar heating, solar photovoltaic conversion, and window insulation. We have used rf sputtering to prepare two types of films: TiO2/Ag/TiO2 and Sn-doped In2O3. To characterize the properties of heat-mirror films for solar-energy collection, we define the parameters αeff, the effective solar absorptivity, and ∊eff, the effective ir emissivity. For our Sn-doped In2O3 films, αeff/∊eff is comparable to the values of α/∊ reported for the leading selective absorbers. Even higher values of αeff/∊eff are obtained for the TiO2/Ag/TiO2 films.
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C. M. Horwitz · Optics Communications · 1974 · 63 citations
Natural Sciences, Materials Engineering, Materials Science +12