Paladugu Sreya, Abdullahi Ibrahim Munkaila, Singh Harish, Spinuzzi Sam, Nath Manashi, Page Katharine
Department of Materials Science and Engineering, University of Tennessee, Knoxville, Tennessee 37996, United States.
Department of Chemistry, Missouri University of Science and Technology, Rolla, Missouri 65409, United States.
ACS Appl Mater Interfaces. 2024 Feb 14;16(6):7014-7025. doi: 10.1021/acsami.3c14977. Epub 2024 Feb 3.
Developing highly active and stable electrocatalysts for the oxygen evolution reaction (OER) is key to improving the efficiency and practical application of various sustainable energy technologies including water electrolysis, CO reduction, and metal air batteries. Here, we use evaporation-induced self-assembly (EISA) to synthesize highly porous fluorite nanocatalysts with a high surface area. In this study, we demonstrate that a 50% rare-earth cation substitution for Ce in the CeO fluorite lattice improves the OER activity and stability by introducing oxygen vacancies into the host lattice, which results in a decrease in the adsorption energy of the OH* intermediate in the OER. Among the binary fluorite compositions investigated, NdCeO is shown to display the lowest OER overpotential of 243 mV, achieved at a current density of 10 mA cm, and excellent cycling stability in an alkaline medium. Importantly, we demonstrate that rare-earth oxide OER electrocatalysts with high activity and stability can be achieved using the EISA synthesis route without the incorporation of transition and noble metals.
开发用于析氧反应（OER）的高活性和稳定的电催化剂是提高包括水电解、CO还原和金属空气电池在内的各种可持续能源技术的效率和实际应用的关键。在此，我们使用蒸发诱导自组装（EISA）来合成具有高表面积的高度多孔萤石纳米催化剂。在本研究中，我们证明在CeO萤石晶格中用50%的稀土阳离子取代Ce，通过将氧空位引入主体晶格来提高OER活性和稳定性，这导致OER中OH*中间体的吸附能降低。在所研究的二元萤石组合物中，NdCeO在10 mA cm的电流密度下显示出最低的OER过电位243 mV，并在碱性介质中具有优异的循环稳定性。重要的是，我们证明使用EISA合成路线可以实现具有高活性和稳定性的稀土氧化物OER电催化剂，而无需引入过渡金属和贵金属。
