AUTHOR=Senguttuvan Premkumar , Lee Eungje , Key Baris , Johnson Christopher S. 

TITLE=Synthesis, structural and electrochemical properties of V4O9 cathode for lithium batteries

JOURNAL=Frontiers in Chemistry

VOLUME=11

YEAR=2023

URL=https://www.frontiersin.org/journals/chemistry/articles/10.3389/fchem.2023.1161053

DOI=10.3389/fchem.2023.1161053

ISSN=2296-2646

ABSTRACT=<p>Single-phase three-dimensional vanadium oxide (V<sub>4</sub>O<sub>9</sub>) was synthesized by reduction of V<sub>2</sub>O<sub>5</sub> using a gas stream of ammonia/argon (NH<sub>3</sub>/Ar). The as-synthesized oxide, prepared by this simple gas reduction method was subsequently electrochemically transformed into a disordered rock salt type-“Li3.7V4O9” phase while cycling over the voltage window 3.5 to 1.8 V versus Li. The Li-deficient phase delivers an initial reversible capacity of ∼260 mAhg<sup>−1</sup> at an average voltage of 2.5 V vs. Li<sup>+</sup>/Li<sup>0</sup>. Further cycling to 50 cycles yields a steady 225 mAhg<sup>−1</sup>. <italic>Ex situ</italic> X-ray diffraction studies confirmed that (de) intercalation phenomena follows a solid-solution electrochemical reaction mechanism. As demonstrated, the reversibility and capacity utilization of this V<sub>4</sub>O<sub>9</sub> is found to be superior to battery grade, micron-sized V<sub>2</sub>O<sub>5</sub> cathodes in lithium cells.</p>