Effect of Doping and Nanostructuring on Properties of perovskite oxide catalysts for oxygen evolution

非技术描述：可充电的金属-空气电池和水分离系统是未来清洁和安全能源的最有前途的技术；前者将成为未来电子设备和电动汽车的电源，而后者将是储存可再生能源的最有效选择。然而，贵金属基析氧反应(OER)催化剂的稀缺性和高成本阻碍了这些技术的商业化。本项目旨在深入了解掺杂和纳米结构工程对廉价钙钛矿催化剂OER活性的影响。采用实验和计算相结合的方法来揭示OER的机理，以开发低成本的OER催化剂，用于新一代金属-空气电池和水分离系统，并显著提高其性能。该项目的结果通过同行评议的出版物广泛传播，新的科学知识预计将对其他化学和能源转换过程的钙钛矿型电催化剂的合理设计产生重大影响。这些新知识也被纳入佐治亚理工学院提供的课程。学生正在接受多学科环境的培训，毕业生通常会在新能源领域找到工作。技术细节：在OPANDO中精心设计的拉曼光谱与电化学测量相结合，以及基于密度泛函理论的计算，研究了两种模型氧化物催化剂：单钙钛矿和双钙钛矿表面的电化学过程。这些模型材料将通过阳离子取代和纳米结构工程进行修饰，以探索其对OER活性和耐久性的影响。在歌剧中，拉曼光谱非常适合在实际操作条件下探测电催化剂的表面化学和结构。表面特征与电化学行为之间的直接关联对于深入了解钙钛矿催化剂上OER的机理和动力学是至关重要的，为基于知识的设计和受控合成用于下一代储能和转换系统的高效和坚固的OER电催化剂提供了科学依据。一名研究生和两名本科生在该项目中担任研究助理；学生们正在获得尖端的歌剧刻画技术方面的宝贵经验。

NON-TECHNICAL DESCRIPTION: Rechargeable metal-air batteries and water splitting systems are the most promising technologies for a clean and secure energy future; the former will be the power source for future electronic devices and electric vehicles while the latter will be the most efficient option for storage of renewable energy. However, the commercialization of these technologies is hindered by the scarcity and high cost of noble metal-based catalysts for oxygen evolution reaction (OER). This project seeks to gain a profound understanding of the effect of doping and nanostructure engineering on OER activity of inexpensive perovskite catalysts. A combination of experimental and computational approaches is used to unravel the mechanisms of OER in order to develop low-cost OER catalysts for a new generation of metal-air batteries and water splitting systems with dramatically enhanced performance. The results of the project are widely disseminated through peer-reviewed publications, and the new scientific knowledge is expected to have a significant impact on the rational design of perovskite electro-catalysts for other chemical and energy transformation processes. The new knowledge is also being incorporated into courses offered at Georgia Tech. Students are being trained in a multidisciplinary environment and graduates typically find employment in the new energy sector.TECHNICAL DETAILS: Carefully designed in operando Raman spectroscopy is combined with electrochemical measurements, together with DFT-based calculations, to investigate the electrochemical processes at the surfaces of two model oxide catalysts: a single perovskite and a double perovskite. These model materials will then be modified by cation substitution and nanostructure engineering to explore the effect on OER activity and durability. In operando Raman spectroscopy is ideally suited for probing surface chemistry and structure of electro-catalysts under realistic operating conditions. The direct correlation between the surface features and the electrochemical behavior is vital to gaining critical insights into the mechanism and kinetics of OER on perovskite catalysts, providing scientific basis for knowledge-based design and controlled synthesis of highly-efficient and robust OER electro-catalysts for next-generation energy storage and conversion systems. One graduate student and two undergraduate students are working as research assistants on the project; the students are gaining valuable experience with cutting-edge in operando characterization techniques.