Fabrication and characterization of conductive polyaniline-decorated Na3V2(PO4)3 cathode for Na-ion batteries

NASICON-structured Na3V2(PO4)3 (NVPO) has been regarded as an advanced electrode for Na-ion storage due to the high theoretical capacity. Unfortunately, the pristine NVPO possesses a bad electrical conductivity and a slow Na+ mobility. Herein, polyaniline-enhanced NVPO (NVPO@PANI) nanocomposite is firstly prepared through the sol-gel way followed by an in-situ aniline polymerization process. Benefiting from the small NVPO crystals and constructed polyaniline film, the transportation of Na+ and electron in NVPO@PANI has been greatly improved. Therefore, the fabricated NVPO@PANI cathode displays outstanding sodium storage performance. It delivers an initial capacity of 114.9 mAh g−1 at 0.1C, and it also present a good cyclic-life with a capacity ratio of about 95.1% at 20C over 500 cycles. The present study offers a prospective strategy for improving the electrochemical property of other electrodes for Na-ion batteries.