A DFT Study of Heteroatom Doped-Pyrazine as an Anode in Sodium ion Batteries

Abstract

Lithium ion batteries cannot satisfy increasing demand for energy storage. A range of complementary batteries are needed which are environmentally acceptable, of moderate cost and easy to manufacture/recycle. In this case, we have chosen pyrazine to be used in the sodium ion batteries to meet the energy storage requirements of tomorrow. Pyrazine is studied as a possible anode material for bio-batteries, lithium-ion, and sodium ion batteries due to its broad set of useful properties such as ease of synthesis, low cost, ability to be charge-discharge cycled, and stability in the electrolyte. The heteroatom doped-pyrazine with atoms of boron, fluorine, phosphorous, and sulphur as an anode in sodium ion batteries has improved the stability and intercalation of sodium ions at the anode. The longest bond observed between sodium ion and sulphur-doped pyrazine at 2.034 Å. The electronic charge is improved and further enhanced by the presence of highly electronegative atoms such as fluorine and bromine in an already electron-attracting pyrazine compound. The highest adsorption energy is observed for the boron-doped pyrazine at -2.735 eV. The electron-deficient sites present in fluorine and bromine help in improving the electronic storage of the sodium ion batteries. A mismatch is observed between the adsorption energy and bond length in pyrazine doped with fluorine and phosphorus.