Metal-Phosphates-Based Materials for Hybrid Supercapacitors

Battery materials provide higher capacity than double-layer ones. However, most part of high-capacity materials suffers from intrinsic kinetics problems, due to phase transitions, slow solid diffusion and low electronic conductivity, which makes them often unsuitable for high-power devices [1]. Some of the strategies to improve the kinetics are to coat the particles with a thin carbon layer (to enhance the electronic conductivity), to reduce the particles (to shorten the solid ionic diffusion) or to tune the structure by metal doping with the aim of suppressing phase transitions [2, 3].<br/>Metal phosphates, with the advantages of abundance, environmental friendliness and low cost are emerging as promising faradaic electrode materials. Herein we will present strategies to convert the battery-like features of materials such as M₃V₂(PO₄)₃ (M=Li, Na, K) to pseudocapacitive-like ones by suppressing their phase transitions [4]. <br/> <br/><b>References</b><br/>[1] R. Tian1, S.-H. Park, P. J. King, G. Cunningham, J. Coelho, V. Nicolosi & J. N. Coleman, Nature Communications (2019)<br/>[2] M. Secchiaroli, G. Giuli, B. Fuchs, R. Marassi, M. Wohlfahrt-Mehrens and S. Dsoke, J. Mater. Chem. A, 3, (2015) 1180<br/>[3] N. Sabi, A. Sarapulova, S. Indris, S. Dsoke, Z. Zhao,M. Dahbi, H. Ehrenberg, I. Saadoune, ChemElectroChem 6 (2019) 892–903.<br/>[4] Q. Fu, S. Liu, A. Sarapulova, L. Zhu, M. Etter, E. Welter, P.G. Weidler, M. Knapp, H. Ehrenberg, S. Dsoke, Adv. Energy Mater. 9 (2019) 1901864.<br/> <br/><b>Acknowledgments</b><br/>This work contributes to the research performed at CELEST (Center for Electrochemical Energy Storage Ulm-Karlsruhe) and was funded by the German Research Foundation (DFG) under Project ID 390874152 (POLiS Cluster of Excellence).