▎ 摘　　要

NOVELTY - A sandwich structure multiphase nanocomposite material comprises three-dimensional reduced graphene oxide nanosheets, and iron disulfide/iron (III) oxide heterojunction nanoparticles coupled and embedded in the three-dimensional reduced graphene oxide nanosheets. The nanocomposite material contains 37.81-42.71 wt.% iron and 4.63-10.27 wt.% sulfur. USE - Sandwich structure multiphase nanocomposite material used in electrochemical energy storage application (claimed) including pseudosupercapacitor. ADVANTAGE - The three-dimensional reduced graphene oxide nanosheets have high specific surface area, rich pore structure and good electrical conductivity, which effectively promotes the rapid transmission of electrons in the electrolyte. The nanosheets ensure that the nanoparticles have better dispersion uniformity, avoid their aggregation, provide more electrochemically active sites, and further improve the electrochemical performance of the composite material. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for a preparation of the sandwich structure multiphase nanocomposite material, which involves mixing graphene oxide, fumaric acid, soluble iron salt and water to obtain a dispersion (I), subjecting the dispersion (I) to a hydrothermal reaction (a1) to obtain a precursor material, mixing the precursor material, thioacetamide and water to obtain a dispersion (II), and subjecting dispersion (II) to a hydrothermal reaction (a2). The mass ratio of the precursor material and thioacetamide is 1: (0.5-1.4).