报告题目：Oxygen Electrocatalysis on Transition Metal SpinelOxides
报告人：Assoc. Prof. Zhichuan J. Xu（徐梽川）
Nanyang TechnologicalUniversity, Singapore
报告时间：2018年4月30日 (周一) 上午10:30-11:30
报告人简介：Zhichuan is an associate professor in School of Materials Science and Engineering,Nanyang Technological University. He received his PhD degree inElectroanalytical Chemistry at 2008 and B.S. degree in Chemistry at 2002 fromLanzhou University, China. His PhD training was received in Lanzhou University(2002-2004), Institute of Physics, CAS (2004-2005), and Brown University(2005-2007). Since 2007, he worked in State University of New York atBinghamton as a Research Associate and from 2009 he worked in MassachusettsInstitute of Technology as a Postdoctoral Researcher. Dr. Xu is member ofInternational Society of Electrochemistry (ISE) and The ElectrochemistrySociety (ECS), and Fellow of The Royal Society of Chemistry (FRSC).He served as a guest editor for the special issue ICEI2016 ofElectrochimica Acta. He also services as an associate editor for Nano-MicroLetters and the vice president of ECS Singapore Section.
Abstract：Exploring efficient and low cost oxygen electrocatalysts for ORR andOER is critical for developing renewable energy technologies like fuel cells,metal-air batteries, and water electrolyzers. This presentation will presents asystematic study on oxygen electrocatalysis (ORR and OER) of transition metalspinel oxides. Starting with a model system of Mn-Co spinel, thepresentation will introduce the correlation of oxygen catalytic activities ofthese oxides and their intrinsic chemical properties. The catalytic activitywas measured by rotating disk technique and the intrinsic chemical propertieswere probed by synchrotron X-ray absorption techniques. It was found thatmolecular orbital theory is able to well-explain their activities. Theattention was further extended from cubic Mn-Co spinels to tetragonal Mn-Co spinelsand it was found that the molecular theory is again dominant in determining thecatalytic activities. This mechanistic principle is further applied to explainthe ORR/OER activities of other spinels containing other transition metals (Fe,Ni, Zn, Li, and etc.).
Figure 1.Octahedral site in spinel isinfluential in determining its oxygen electrocatalysis.