Programme

P.62 -- Poster, VCTP-46

Date: Wednesday, 6 October 2021

Time: 08:30 - 10:00

Na$_2$V$_3$(SO$_4$)$_4$ - a promissing cathode material of SIB batteries

Thien Lan Tran1, Viet Bac Phung2, and Van An Dinh3*

1 Department of Physics, Hue University of Education, Hue University, 34 Le Loi St., Hue, Vietnam 2 Institute of Sustainability Science, VNU Vietnam Japan University, Luu Huu Phuoc St., My Dinh I, Hanoi, Vietnam 3 Department of Precision Engineering, Graduate School of Engineering, Osaka University, 2-1 Yamadaoka, Suita, Osaka 565-0871, Japan

In this report, based on the Density Functional Theory we propose a new cathode material Na$_2$V$_3$(SO$_4$)$_4$ for SIB batteries. The crystal structure, electronic structure, open-circuit potential, polaron formation in the defected structure, and the possible diffusion processes are explored by the method GGA+U with $U_\text{eff} = 3.5$ eV. Diffusion processes are investigated systematically with considering the simultaneously migration of accompanying polarons of Na-vacancies [1]. Results depict that with the crystal structure refined in the $Cmc2_1$ group [2], the compound posseses a bandgap of 2.38 eV, a redox potential of 3.35 V and an activation energy of 686 meV. With the relatively high redox potential and low activation energy, Na$_2$V$_3$(SO$_4$)$_4$ is expected to be a promissing cathode material for SIB batteries. [1] Dinh, V. A. et al. Appl. Phys. Express 5 (2012) 045801. [2] Gao, J. et al; J. Mat. Chem. A 4 (2016) 11870.

Presenter: Trần Thiện Lân