SrFeO3 peculiarities and exploitation in decontamination processes and environmentally-friendly energy applications

Abstract

New technologies have been developed to avoid ecological damages by promoting depollution and eco-friendly synthesis routes of chemicals and materials, and setting efficient “cleaner” energy supply methods. These research fields, strongly interconnected, can contribute to sustainable technological advancement and represent the frame in which SrFeO3-based materials can act as valuable tools. SrFeO3 is a ABO3 perovskite-type mixed oxide, widely studied in nanotechnology. Its pristine form does not contain expensive elements, such as rare and noble metals, or toxic components. SF peculiar features, such as non-stoichiometric composition (oxygen vacancies), the unusual oxidation state of Fe4+ and the related transformations of structural, electronic and magnetic characteristics, are attracting many research teams. This review summarizes most of these fundamental aspects, adding tips on some of the possible SF modification strategies and characterization techniques in view of environmental-benign applications. Particularly, thanks to SF-based materials’ oxygen exchange properties, ionic and electronic conduction abilities and catalytic activities, SFs are used in: (i) depollution processes as adsorbents, photo- and thermo-catalysts, combustion catalysts, antimicrobial agents, (ii) alternative devices for energy production and storage, and (iii) efficient systems for fuel conversion (i.e., chemical looping). The main correlations among SF composition, physical-chemical properties, performances and stability will be highlighted. This way, this review addresses indications to create SF-based tailored and functional materials specifically for the environment and energy, which are still underestimated and often replaced by other well-known oxides such as Lanthanum-based (in A-site) or Co, Ti-based (in B-site) perovskites.