Construction of conductive network in hematite for lithium, sodium and potassium storage

Abstract In this work, a reduction roasting strategy was adopted to transform hematite into powerful anode materials to store lithium (Li), sodium (Na) and potassium (K). This strategy aimed to construct conductive porous structure on pristine hematite particles and could be generalized to other oxide anodes. The free volume of porous structure could cushion the volume changes, improve its accessibility to Li+, Na+, K+ ions, and shorten ionic diffusion pathways. Therefore, these newly-designed anodes were discharged and charged to test their storage capacity, cycling stability as well as rate performances. Their cyclic voltammetry curves and electrochemical impedance spectra were also measured to unravel ion-storage mechanisms.