Design of All-Oxide Multilayers with High-Temperature Stability Toward Future Thermophotovoltaic Applications

Thermophotovoltaic (TPV) technology converts heat into electricity using thermal radiation. Increasing operating temperature is a highly effective approach to improving the efficiency of TPV systems. However, most reported TPV selective emitters degrade rapidly via. oxidation as operating temperatures increase. To address this issue, replacing nanostructured oxide-metal films with oxide-oxide films is a promising way to greatly limit oxidation, even under high-temperature conditions. This study introduces new all-oxide photonic crystal designs for high-temperature stable TPV systems, overcoming limitations of metal phases and offering promising material choices. The designs utilize both yttria-stabilized zirconia (YSZ)/MgO and CeO2/MgO combinations with a multilayer structure and stable high-quality growth. Both designsexhibit positive optical dielectric constants with tunable reflectivity, measured via optical characterization. Thermal stability testing using in situ heating X-ray diffraction (XRD) suggests high-temperature stability (up to 1000 degrees C) of both YSZ/MgO and CeO2/MgO systems. The results demonstrate a new and promising approach to improve the high-temperature stability of TPV systems, which can be extended to a wide range of material selection and potential designs. Increasing operating temperature is a highly effective approach to improving the efficiency of thermophotovoltaic (TPV) systems. However, most reported TPV systems degrade rapidly via oxidation at high temperatures. Replacing nanostructured oxide-metal films with oxide-oxide films is a promising way to greatly limit oxidation, even under high-temperature conditions. In this work, a new all-oxide design (yttria-stabilized zirconia(YSZ)/MgO, CeO2/MgO) with a multilayer structure is reported. Both designs behave as optical dielectrics with tunable reflectivity, measured via optical characterization. Thermal stability testing suggests high-temperature stability up to 1000 degrees C. The results demonstrate a new and promising approach to improve the high-temperature stability of TPV systems, which can be extended to a wide range of material selection and design potentials.image