High thermal radiation of Ca-doped lanthanum chromite

Calcium-doped lanthanum chromite, La1-xCaxCrO3, was prepared using a solid-state reaction method, and the effect of varying the Ca content (0 <= x <= 0.5) was investigated in relation to its crystalline structure, surface morphology, solar absorption and thermal radiation. This found that the crystalline structure is slightly distorted by Ca2+ doping, with an accompanying increase in the valence state of Cr ions and oxygen vacancies enhancing both the solar absorption and thermal emittance. Overall, the La1-xCaxCrO3 system displays relatively high thermal radiation properties, with an optimal composition of La0.5Ca0.5CrO3 exhibiting a solar absorption of 95% and a thermal emittance of 0.94. When used as a light absorber coupled to a thermoelectric module this proved capable of generating electricity and hot water, thereby demonstrating the suitability of this energy-saving material for use in solar thermal radiation applications.