主讲人：徐杨，伦敦大学副教授
时 间：2025年2月27日 10:00
地 点：物电学院A栋217
联系人：鲁兵安
讲座摘要：Developing alternative energy storage technologies beyond lithium has become a prom inent slice of global energy research portfolio, shaping future electrified mobility, the utilization of renewable energies, and large-scale stationary energy storage. Na-ion batteries (NIBs) are receiving global attention in recent years due to the announcement of commercializing products by some of the largest NIB manufactures in the world, while the development of K-ion and Ca-ion batteries (KIBs and CIBs) is at an early stage. Understanding charge storage mechanism is crucial for the performance improvement of post-Li battery technologies. In this talk, I will first discuss utilizing K-ion battery cathodes, K-pre-intercalated Prussian blue analogs (K-PBAs), as NIB cathodes. I will show that having a level of [Fe(CN)6]4- anion vacancies in K-PBAs can maximize K-ion intercalation and minimize Na-ion intercalation, which results in the increase in discharge voltages and rate capability. Also, when utilizing K-PBAs and Na-PBAs in Ca-ion batteries, K-ion/Na-ion intercalation is preferred by the PBA structure over Ca-ion intercalation even in the Ca-ion electrolyte. This is a profound effect that has been overlooked in the literature of Ca-ion batteries. As a result, Ca-ion intercalation can be enhanced when the K-ion/Na-ion content in the pristine PBAs is reduced, shifting to a Ca/K or Ca/Na co-intercalation process. Then, I will discuss our recent investigation of the K-ion storage mechanism in commercial MoS2, which has not been exclusively investigated and therefore remains unclear. I will show that the conversion reaction of MoS2 is partially reversible and accompanied by S anionic redox reactions with K and furthermore, the reaction pathway differs when operating via different charge/discharge routes. By controlling the routes, dual reactions of cationic Mo and anionic S redox take place simultaneously, which can improve the stability of the MoS2 anode while maintaining K-S battery chemistry.
主讲人简介：Dr Yang Xu is an Associate Professor in Energy Storage in the Department of Chemistry at University College London (UCL), UK. He received his PhD at the University of Science and Technology of China (USTC) under the supervision of Prof. Yi Xie. He then carried out his postdoctoral research at Boston College (US) and the University of Alberta (Canada) and worked as a Senior Scientist at the Technical University of Ilmenau (Germany). He joined UCL Chemistry as a Lecturer in 2019 and became an Associate Professor in 2023. His research focuses on next-generation battery materials and chemistries, with special interest in cation intercalation mechanism, electrochemical metal deposition, and anionic redox activity. He has received research fundings from various funders including the Engineering and Physical Sciences Research Council (EPSRC), the Faraday Institution, the Royal Society, the Science and Technology Facilities Council (STFC), the Leverhulme Trust, and UCL. He is the recipient of MINE Outstanding Young Scientist Award (2019), EPSRC New Investigator Award (2020), and STFC Early Career Award (2023). He is a member of the editorial board of the Journal of Physics: Energy (IOP) and the advisory boards of the Journal of Materials Chemistry A and Materials Advances (RSC) as well as ACS Applied Energy Materials (ACS).
