Modifying La0.6Sr0.4MnO3 Perovskites with Cr Incorporation for Fast Isothermal CO2‐Splitting Kinetics in Solar‐Driven Thermochemical Cycles. Issue 28 (21st June 2019)

• Record Type: Journal Article
• Authors: Carrillo, Alfonso J.; Bork, Alexander H.; Moser, Thierry; Sediva, Eva; Hood, Zachary D.; Rupp, Jennifer L. M.
• Is Part Of: Advanced energy materials. Volume 9:Issue 28(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-06-21
• Subjects: isothermal -- kinetics -- perovskites -- solar fuels -- thermochemical; Energy harvesting -- Materials -- Periodicals; Energy conversion -- Materials -- Periodicals; Energy storage -- Materials -- Periodicals; Photovoltaics -- Periodicals; Fuel cells -- Periodicals; Thermoelectric materials -- Periodicals; 621.31
• DOI: 10.1002/aenm.201803886
• Languages: English
• ISSNs: 1614-6832

Abstract

Abstract: Perovskites are promising oxygen carriers for solar‐driven thermochemical fuel production due to higher oxygen exchange capacity. Despite their higher fuel yield capacity, La0.6 Sr0.4 MnO3 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 La0.6 Sr0.4 MnO3 is explored based on thermodynamic calculations that suggest an enhanced driving force toward CO2 splitting at high temperatures for La0.6 Sr0.4 Cr x Mn1− x O3 perovskites. Here, reported is a threefold faster CO fuel production for La0.6 Sr0.4 Cr0.85 Mn0.15 O3 compared to conventional La0.6 Sr0.4 MnO3, 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. Abstract : It is demonstrated that incorporation of Cr cations partially substituting Mn in La0.6 Sr0.4 Cr x Mn1‐ x O3 improves the CO2 ‐splitting rate in solar‐driven thermochemical cycles for syngas production. CO production is especially enhanced under isothermal cycling schemes, T red = T ox = 1400 °C, with x = 0.85 exhibiting threefold faster reaction rates than x = 0 and twofold faster than CeO2 .