Study of humboldtine for sodium battery anode

Abstract

The search for new cheap materials for sodium-ion batteries is very important for theoretical research and practical application. In this paper, the applicability of the mineral Humboldtine as an anode material in sodium-ion batteries is discussed. Using molecular modeling based on DFT, as implemented in the QUANTUM ESPRESSO computing package, the electrochemical activity of Humboldtine intercalated with a Sodium atom is estimated, as well as a change in the band gap width depending on dehydration, and then intercalation of Sodium into Humboldtine. The electrochemical parameters obtained earlier for Lithium intercalation, such as adsorption energy and Open Circuit Voltage(OCV ), are also compared with the values obtained in this work on the intercalation of Humboldtine with Sodium. The analysis shows that in the case when water is removed from the Humboldtine structure, the value of the band gap changes from 2.05 eV to 0.63 eV. Further, as a result of intercalation of dehydrated Humboldtine with a Sodium atom, the value increases to 1.18 eV. The electrochemical parameters calculated for Humboldtine intercalated with a Sodium atom were equal to Eads = -2.35 eV and OCV = 1.22 V, respectively. The results show that the voltage of the Na-ion battery was less than that of the lithium-ion battery, and it is better to use a lower voltage for the anodes.