The establishment of structure-performance relationship of heterogeneous catalysts is highly desirable for catalyst design and understanding of nature of active sites. As a case study, lower olefins synthesis directly from CO₂ hydrogenation (CTO) has been performed over iron catalyst. Structure evolution of the iron catalyst during the life cycle for CTO, i.e. generation → reaction → deactivation → regeneration, was studied comprehensively. Particularly, operando techniques allowed directly observing the continuous phase transition of Fe₅C₂→Fe₃C→Fe₃O₄→Fe₅C₂ over the working catalyst in a 140-h cycle. This study not only reveals the dynamic structure evolution of iron catalyst during the full life cycle, but also endows deep insights into the underlying the mechanism, especially the deactivation mechanism, thus paves the way for the rational design of next-generation industrial catalysts. 

Key words: operando techniques, iron catalyst, full life cycle, deactivation mechanism, structure evolution.

Dr. Xu received her bachelor and master degree in Chemical Engineering from Tianjin University in 1997 and 2003, respectively. After obtaining her PhD from National University of Singapore (Singapore) in 2009, she worked as a postdoctoral fellow at National University of Singapore. Currently, she is professor of chemical engineering at East China University of Science and Technology since Sep. 2014. 

Dr. Xu is interested in synthesis, evaluation of catalytic performance, and in-situ/operando characterization of nanocatalysts in energy and environmental field. Dr Xu has co-authored more than 70 peer-review papers in high impact factor journals, 2 book chapters, and 16 patents. She also has more than 20 conference contributions in international congresses. Up to now, she is the Principal Investigator of 16 projects.