Effect of Mn on lithium-sulphate-borated based glass as energy storage applications

Abstract Li2S-2H3BO3 glasses with and without 4 mol% MnO2 dopant were successfully synthesized. The effect of manganese doping in glasses were studied by XRD, TEM, and UV-Vis, respectively. The magnetism of glasses were measured by vibrating sample magnetometer (VSM). The parent glass exhibited mixed behaviors between ferromagnetism and diamagnetism, while ferromagnetism and paramagnetism were observed for glass doped with 4 mol % of MnO2. The electrochemical properties of vitreous cathodes were studied by cyclic voltammetry (CV). Interestingly, glasses doped with MnO2 show better pseudocapacitive behavior with the highest specific capacitance of ~49 F.g−1 at scan rate of 5 mV.s−1. Furthermore, the valence states of Mn and S in glasses were investigated by XANES. Mixing oxidation states of Mn2+/Mn3+ ions was observed and the S6+ ions with 6-fold oxygen coordinated network around S atoms was revealed. The existing of sulfur atoms in glass system was enhanced conductivity by substitution into oxygen vacancy.