EUROPEAN CONGRESS AND EXHIBITION ON ADVANCED MATERIALS AND PROCESSES - EUROMAT 2021

The growing demand for energy leads to increasing interest in efficient and sustainable large-scale energy storage systems. Among different energy storage systems, electrochemical batteries are among the most convenient, efficient and practical. Aqueous rechargeable Na-ion batteries (NIBs) are expected to become one of the alternatives to conventional Li-ion batteries systems. Various novel materials have been investigated and reported as cathodes and anodes for aqueous NIBs, however there are still several problems such poor cycle stability, low energy density or low voltage which should be acknowledged [1]. After all, Mn-based (mixed)phosphate cathodes have a lot of advantages such as widespread availability of raw materials, low cost, high safety and non-toxicity. Moreover, Mn-based framework materials distinguish themselves as good candidates for fast sodium intercalation, small lattice volume changes and high insertion potentials [2,3].

In this work, we synthesized a number of different Mn-based (mixed) phosphate framework materials such as Na4Mn3(PO4)2(P2O7), Na3MnPO4CO3 and Na3MnTi(PO4)3 via solid-state or hydrothermal synthesis methods. The structure and morphology of prepared materials were characterized by X-ray diffraction, scanning electron microscopy and thermogravimetric analysis. The electrochemical properties of prepared electrodes were investigated by cyclic voltammetry and charge/discharge galvanostatic cycling and impedance spectroscopy.

Acknowledgements: This project has received funding from the European Regional Development Fund (Project No. 01.2.2-LMT-K-718-02-0005) under grant agreement with the Research Council of Lithuania (LMTLT).

References:
[1] Y. Liu, Adv. Funct. Mater 2021, 2010445.
[2] J. Kang, ACS Sustain. Chem. Eng. 2020, 8, 163-171.
[3] H. Kim, Energy Environ. Sci. 2015, 8, 3325-3335.