文献类型：期刊文献

英文题名：Ru-promoted perovskites as effective redox catalysts for CO2 splitting and methane partial oxidation in a cyclic redox scheme

作者：Iftikhar, Sherafghan[1];Martin, William[1];Wang, Xijun[1];Liu, Junchen[1];Gao, Yunfei[1,2];Li, Fanxing[1]

机构：[1]North Carolina State Univ, Dept Chem & Biomol Engn, Raleigh, NC 27695 USA;[2]East China Univ Sci & Technol, Shanghai Engn Res Ctr Coal Gasificat, Key Lab Coal Gasificat & Energy Chem Engn, Minist Educ, Shanghai 200237, Peoples R China

年份：2022

卷号：14

期号：48

起止页码：18094

外文期刊名：NANOSCALE

收录：;EI(收录号：20225013253682);WOS:【SCI-EXPANDED(收录号:WOS:000892516100001)】；

基金：This work was supported by the National Science Foundation (CBET -1923468), the U.S. Department of Energy (Award DE-FE0031703), and the North Carolina State University Kenan Institute for Engineering, Technology and Science. The characterization work was performed in part at the Duke University Shared Materials Instrumentation Facility (SMIF). It was also performed in part at the Analytical Instrumentation Facility (AIF) at North Carolina State University, which is supported by the State of North Carolina and the National Science Foundation (award number ECCS-2025064). Both the SMIF and AIF are members of the North Carolina Research Triangle Nanotechnology Network (RTNN), a site in the National Nanotechnology Coordinated Infrastructure (NNCI).

语种：英文

外文关键词：Catalyst deactivation - Design for testability - Lanthanum compounds - Methane - Oxidation - Perovskite - Ruthenium compounds - Thermodynamics

摘要：The current study reports AxA '1-xByB '1-yO3-delta perovskite redox catalysts (RCs) for CO2-splitting and methane partial oxidation (POx) in a cyclic redox scheme. Strontium (Sr) and iron (Fe) were chosen as A and B site elements with A ' being lanthanum (La), samarium (Sm) or yttrium (Y), and B ' being manganese (Mn) or titanium (Ti) to tailor their equilibrium oxygen partial pressures (PO2s) for CO2-splitting and methane partial oxidation. DFT calculations were performed for predictive optimization of the oxide materials whereas experimental investigation confirmed the DFT-predicted redox performance. The redox kinetics of the RCs improved significantly by 1 wt% ruthenium (Ru) impregnation without affecting their redox thermodynamics. Ru-impregnated LaFe0.375Mn0.625O3 (A = 0, A ' = La, B = Fe, and B ' = Mn) was the most promising RC in terms of its superior redox performance (CH4/CO2 conversion >90% and CO selectivity similar to 95%) at 800 degrees C. Long-term redox testing over Ru-impregnated LaFe0.375Mn0.625O3 indicated a stable performance during the first 30 cycles followed by an similar to 25% decrease in the activity during the last 70 cycles. Air treatment was effective to reactivate the redox catalyst. Detailed characterizations revealed the underlying mechanism of the redox catalyst deactivation and reactivation. This study not only validated a DFT-guided mixed oxide design strategy for CO2 utilization but also provides potentially effective approaches to enhance redox kinetics and long-term redox catalyst performance.