Modifying La0.6Sr0.4MnO3 Perovskites with Cr Incorporation for Fast Isothermal CO2‐Splitting Kinetics in Solar‐Driven Thermochemical Cycles

Abstract

AbstractPerovskites are promising oxygen carriers for solar‐driven thermochemical fuel production due to higher oxygen exchange capacity. Despite their higher fuel yield capacity, La0.6Sr0.4MnO3 perovskite materials present slow CO2‐splitting kinetics compared with state‐of‐the‐art CeO2. In order to improve the CO production rates, the incorporation of Cr in La0.6Sr0.4MnO3 is explored based on thermodynamic calculations that suggest an enhanced driving force toward CO2 splitting at high temperatures for La0.6Sr0.4CrxMn1−xO3 perovskites. Here, reported is a threefold faster CO fuel production for La0.6Sr0.4Cr0.85Mn0.15O3 compared to conventional La0.6Sr0.4MnO3, and twofold faster than CeO2 under isothermal redox cycling at 1400 °C, and high stability upon long‐term cycling without any evidence of microstructural degradation. The findings suggest that with the proper design in terms of transition metal ion doping, it is possible to adjust perovskite compositions and reactor conditions for improved solar‐to‐fuel thermochemical production under nonconventional solar‐driven thermochemical cycling schemes such as the here presented near isothermal operation.