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Title: One Dimensional Nanomaterials for Emerging Energy Storage

Liqiang Mai

Wuhan University of Technology, China

Biography

Liqiang Mai, Changjiang Scholar Chair Professor of Materials Physics and Chemistry, Dean for International Affairs of International School of Materials Science and Engineering at Wuhan University of Technology. He received Ph.D. degree from WUT in 2004 and carried out postdoctoral research in Prof. Zhonglin Wang's group at Georgia Institute of Technology (2006-2007). He worked as an advanced research scholar in Prof. Charles M. Lieber's group at Harvard University (2008-2011) and Prof. Peidong Yang’s group at University of California, Berkeley (2017). Prof. Liqiang Mai is mainly engaged in research field of nano energy materials and micro/nano devices. He has published over 280 papers tagged by SCI in leading journals.

Abstract

One-dimensional nanomaterials can offer large surface area, facile strain relaxation upon cycling and efficient electron transport pathway to achieve high electrochemical performance. Hence, nanowires have attracted increasing interest in energy related fields. We designed the single nanowire electrochemical device for in situ probing the direct relationship between electrical transport, structure, and electrochemical properties of the single nanowire electrode to understand intrinsic reason of capacity fading. The results show that during the electrochemical reaction, conductivity of the nanowire electrode decreased, which limits the cycle life of the devices. We have developed a facile and high-yield strategy for the oriented formation of CNTs from metal−organic frameworks (MOFs). The appropriate graphitic N doping and the confined metal nanoparticles in CNTs both increase the densities of states near the Fermi level and reduce the work function, hence efficiently enhancing its oxygen reduction activity. Then, we fabricated a field-tuned hydrogen evolution reaction (HER) device with an individual MoS2 nanosheet to explore the impact of field effect on catalysis. In addition, we demonstrated the critical role of structural H2O on Zn2+ intercalation into bilayer V2O5·nH2O. The results suggest that the H2O-solvated Zn2+ possesses largely reduced effective charge and thus reduced electrostatic interactions with the V2O5 framework, effectively promoting its diffusion. We also identified the exciting electrochemical properties (including high electric conductivity, small volume change and self-preserving effect) and superior sodium storage performance of alkaline earth metal vanadates through preparing CaV4O9 nanowires. Our work presented here can inspire new thought in constructing novel one-dimensional structures and accelerate the development of energy storage applications.