EAGER: Fe/Mn-Containing Perovskite Oxides Promoted by Alkali Metal Molybdates for Chemical-Looping Catalysis – Thin-Film Preparation and Surface Characterization

EAGER：碱金属钼酸盐促进的含铁/锰钙钛矿氧化物用于化学循环催化 — 薄膜制备和表面表征

• 批准号: 2116724
• 负责人: Fanxing Li
• 金额: $ 30万
• 依托单位: North Carolina State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2024-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2116724&HistoricalAwards=false
• 关键词: EAGER; Fe; Mn; Containing; Perovskite

Natural gas is a key raw material for production of olefins used extensively for the chemical manufacture of polymeric materials. Production of ethylene and propylene is among the most energy-intensive processes in the chemical sector, emitting more than 300 million tons of carbon dioxide each year. The project explores an alternative to current industry practice known as chemical-looping oxidative dehydrogenation (CL-ODH). CL-ODH has potential to substantially increase energy efficiency and lower carbon emissions compared to conventional ODH. The project focuses on improving the performance and durability of CL-ODH catalyst materials by understanding – at a fundamental level – the mechanism by which they work, and by using that understanding to optimize catalyst design. The project focuses on the mechanistic aspects of alkali metal molybdate promoted perovskites oxides, specifically, Na2MoO4, Na2Mo2O7 or K2MoO4 promoted La0.8Sr0.2FeO3 and La0.7Ca0.3MnO3 for CL-ODH of ethane and propane. The CL-ODH concept has potential to greatly intensify light-olefin production. The research team has previously discovered that molybdate promoted perovskite oxides form a core-shell structure with the Mn/Fe-containing perovskite oxide core promoting active lattice oxygen storage/exchange, and the molten molybdate shell facilitating selective C-H bond activation and oxidative conversion. This project represents the first in-depth attempt to investigate the roles of the core, shell, and active species for this novel redox catalyst system. The project aims to unveil the underlying mechanisms for the CL-ODH reactions by preparing thin-film model catalysts and performing extensive characterizations using a variety of surface science tools. Epitaxially grown thin films of La0.8Sr0.2FeO3 and La0.7Ca0.3MnO3 will be prepared on commercially available SrTiO3 via polymer-assisted deposition. This is followed with sequential MBE deposition of MoO3 and Na/K, and O2 ambient treatment. The growth of the thin film will be monitored in situ and characterized afterwards. Mechanistic investigations and reactive testing will be performed on perovskite thin film samples both with and without alkali metal molybdates to establish a rational approach for redox catalyst optimization. Results from the project will be integrated in teaching by the investigators. Through the Kenan fellowship program at North Carolina State University, high school teachers will be involved in the project to stimulate students' interest towards STEM careers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

天然气是用于广泛用于聚合材料化学生产的烯烃的关键原料。乙烯和丙烯的生产是化学部门最能源密集型过程之一，每年排放超过3亿吨二氧化碳。该项目探讨了当前行业实践的替代方法，称为化学循环氧化物脱氢（CL-ODH）。与常规ODH相比，CL-ODH具有大幅提高能效和降低碳排放的潜力。该项目着重于通过理解（在基本层面）它们起作用的机制以及使用该理解来优化催化剂设计来提高CL-ODH催化剂材料的性能和耐用性。该项目着重于碱金属钼酸盐的机械方面促进了钙钛矿氧化物，具体来说，Na2moo4，Na2MO2O7或K2MOO4促进了LA0.8SR0.2FEO3和LA0.7CA0.7CA0.3CA0.3MNO3，用于类似和Propane的Cl-Odh。 CL-ODH概念有可能大力加强光烯烃的生产。研究小组先前已经发现，钼酸盐促进钙钛矿氧化物形成了核壳结构，其中含有Mn/Fe的钙钛矿氧化物氧化物核心促进活性晶格氧的储存/交换，并支持选择性的C-H键激活和氧化转化。该项目代表了研究这种新型氧化还原催化剂系统的核心，壳和活性物种的作用的第一次深入尝试。该项目旨在通过准备薄膜模型催化剂并使用各种表面科学工具来揭示CL-ODH反应的基本机制。 LA0.8SR0.2FEO3和LA0.7CA0.3MNO3的外延生长的薄膜将通过聚合物辅助沉积在市售的SRTIO3上制备。随后是MBE沉积MOO3和Na/K，以及O2环境处理。薄膜的生长将在原位进行监测，并以后进行表征。机械研究和反应性测试将在有或没有碱金属钼酸盐的钙钛矿薄膜样品上进行，以建立一种合理的氧化还原催化剂优化方法。该项目的结果将由研究人员整合到教学中。通过北卡罗来纳州立大学的Kenan奖学金计划，高中教师将参与该项目，以激发学生对STEM职业的兴趣。该奖项反映了NSF的法定任务，并通过使用该基金会的知识分子优点和更广泛的影响来评估NSF的法定任务，并被认为是宝贵的支持。

项目成果

Redox Oxide@Molten Salt as a generalized catalyst design strategy for oxidative dehydrogenation of ethane via selective hydrogen combustion

• DOI: 10.1016/j.apcata.2022.118869
• 发表时间: 2022-09
• 期刊: Applied Catalysis A: General
• 作者: Junchen Liu;S. Yusuf;Daniel Jackson;W. Martin;Dennis Chacko;Kyle Vogt-Lowell;Luke M. Neal

MoO 3 films grown on stepped sapphire (0001) by molecular beam epitaxy

通过分子束外延在阶梯式蓝宝石（0001）上生长MoO 3 薄膜

• DOI: 10.1116/6.0000962
• 发表时间: 2021
• 期刊: Journal of Vacuum Science & Technology A
• 影响因子: 2.9
• 作者: Novotný, Petr;Lamb, H. Henry
• 通讯作者: Lamb, H. Henry

Mixed oxides as multi-functional reaction media for chemical looping catalysis

混合氧化物作为化学链催化的多功能反应介质

• DOI: 10.1039/d2cc05502c
• 发表时间: 2022
• 期刊: Chemical Communications
• 影响因子: 4.9
• 作者: Liu, Junchen;Li, Fanxing
• 通讯作者: Li, Fanxing

Accelerated Perovskite Oxide Development for Thermochemical Energy Storage by a High‐Throughput Combinatorial Approach

• DOI: 10.1002/aenm.202203833
• 发表时间: 2023-03
• 期刊: Advanced Energy Materials
• 影响因子: 27.8
• 作者: R. Cai;Hilal Bektaş;Xijun Wang;Kyle McClintock;Lauren Teague;Kunran Yang;Fanxing Li