Nanohybrids of hematite nanoparticles and reduced graphene oxide nanosheets: Anode materials for lithium ion batteries

Abstract

The nanohybrids of hematite (alpha-Fe2O3) nanoparticles and reduced graphene oxide (rGO) nanosheets were prepared by a facial two-step chemical method. The alpha-Fe2O3 nanoparticles prepared by a sol-gel technique were hybridized with the pristine rGO nanosheets by ultra-sonication-assisted method. The rGO and alpha-Fe2O3 nanoparticles were dispersed in toluene to prepare (rGO)(x)/alpha-Fe2O3 nanohybrids. The crystal structure, vibrational modes, surface morphology, and elemental composition of these (rGO)(x)/alpha-Fe2O3 nanohybrids were investigated. The 3D nanostructure of alpha-Fe2O3 nanoparticles were randomly anchored on cross-linking rGO nanosheets. These rGO nanosheets functioned as mechanical support and an efficient electron conducting pathway in the (rGO)(x)/alpha-Fe2O3 nanohybrids. X-ray diffraction (XRD) spectra confirmed the crystal structure and phase purity while scanning electron microscopy (SEM) images showed the dispersion of alpha-Fe2O3 nanoparticles over rGO nanosheets. The hybridization of rGOs nanosheets with alpha-Fe2O3 nanoparticles significantly enhanced the electrochemical storage performance as anode material for LIBs. The first discharge capacity for the (rGO)(x)/alpha-Fe2O3 nanohybrids of 1469 mAh/gwas much better than that of the bare alpha-Fe2O3 nanoparticles of 895 mAh/g. Cyclic stability was enhanced as the discharge capacity was retained after 100 cycles for the (rGO)(x)/alpha-Fe2O3 nanohybrids. Moreover, the improved rate capability that was also observed for the (rGO)x/alpha-Fe2O3 nanohybrids further authenticates the use of these nanohybrids as anode materials for LIBs.(c) 2022 Elsevier B.V. All rights reserved.