Lanthanum鈥揝trontium鈥揗anganese Perovskites as Redox Materials for Solar Thermochemical Splitting of H2O and CO2

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• 作者：Jonathan R. Scheffe ; David Weibel ; Aldo Steinfeld
• 刊名：Energy & Fuels
• 出版年：2013
• 出版时间：August 15, 2013
• 年：2013
• 卷：27
• 期：8
• 页码：4250-4257
• 全文大小：453K
• 年卷期：v.27,no.8(August 15, 2013)
• ISSN：1520-5029

文摘

A thermodynamic and experimental investigation of a new class of solar thermochemical redox intermediates, namely, lanthanum鈥搒trontium鈥搈anganese perovskites, is presented. A defect model based on low-temperature oxygen non-stoichiometry data is formulated and extrapolated to higher temperatures more relevant to thermochemical redox cycles. Strontium contents of x = 0.3 (LSM30) and x = 0.4 (LSM40) in La_1鈥?i>xSr_xMnO_{3鈭捨?/sub> result in favorable reduction extents compared to ceria in the temperature range of 1523鈥?923 K. Oxidation with CO2 and H2O is not as thermodynamically favorable and largely dependent upon the oxidant concentration. The model is experimentally validated by O2 non-stoichiometry measurements at high temperatures (>1623 K) and CO2 reduction cycles with commercially available LSM35. Theoretical solar鈥揻uel energy conversion efficiencies for LSM40 and ceria redox cycles are 16 and 22% at 1800 K and 13 and 7% at 1600 K, respectively.}