(643h) Catalytic Conversion of CO2 into Solar Fuels Via Thermochemical Cycle Driven By La-Based Perovskites

Fulfillment of the mounting demand of energy by using solar fuels such as solar H2 or solar syngas, produced via catalytic H2O (WS)/CO2 splitting (CS) reactions, is one of the maintainable and viable approaches for harnessing the renewable and plentifully available solar energy. This process exploits the concentrated solar power heat to drive the high-temperature thermal reduction (TR) of metal oxides (MOs). The solar H2 can be used as a gaseous fuel, whereas; the solar syngas can be converted into multiple types of liquid fuels via the Fischer Tropsch process. Effectively, by applying this solar fuel technology, solar energy can be stored as high-grade chemical energy. This stowed chemical energy is more sustainable since it can be transported and stockpiled for a long time without any degradation. Up to the present time, numerous MOs have been considered for both WS and CS reactions which include volatile i.e., zinc oxide and tin oxide and non-volatile MOs i.e., iron oxide, ferrites, ceria, and doped ceria, and hercynite. Among all the MOs investigated, ceria based oxides appear to be the superlative choice as these oxides possess most of the aforementioned attributes. As an alternative to the ceria based oxides, in recent years, perovskite-based oxides were investigated for thermochemical WS/CS reactions. Among the various perovskite oxides, La-based perovskites were examined considerably for the production of both H2 and CO. Based on the literature review, we understood that the previous studies were focused mainly on La-Sr-Mn perovskites and the redox reactivity of these perovskites were estimated by performing only one or two WS/CS cycles. In this study, the thermal reduction and re-oxidation aptitude of La-Sr-Mn-Co-based (LSMC) perovskite were determined (as an alternative for LSM). An entire spectrum of LSMC perovskites was tested by performing multiple CS cycles. The prime reason to conduct this study was to improve the understanding of the thermochemical community towards the application of LSMC perovskites for WS/CS reactions and to compare the obtained results with the state-of-the-art CeO2 and LSM catalytic material.