Surface textured La_0.5Sr_0.5Co_1-2xFe_xNi_xO_3-δ with gradient layer components for high temperature solar thermal conversion

Solar absorbers in the concentrated solar power (CSP) system aim to convert solar radiation into thermal energy efficiently. Currently, challenges still remain on high spectral selectivity together with high operating temperature. Herein, a surface textured ceramic with gradient La_0.5Sr_0.5Co_1-2xFe_xNi_xO_3-δ components was developed to enhance the solar absorption and reduce the radiation heat loss. The solar absorbance and emissivity of the composite ceramic was 0.78 and 0.44, respectively. The average equilibrium temperature of composite ceramic could reach 876 °C under focused solar irradiation intensities of 11.5 W/cm², 11.4 W/cm² and 11.1 W/cm², which was 51 °C higher than that of low emission single-component ceramic with same surface textured structure and 92 °C higher than that of high absorption single-component ceramic with same surface textured structure. These results showed that surface textured ceramic with gradient La_0.5Sr_0.5Co_1-2xFe_xNi_xO_3-δ components could be a promising solar thermal conversion material.