Preparation and characterizations of reduced graphene oxide reinforced silicon composites

Silicon has been potentially considered a promising anode material for lithium-ion batteries (LIBs) due to its high specific capacity to meet the demands of portable energy storage and electric vehicle applications. Reduced graphene oxide (RGO) reinforcement in silicon (Si) emerges as a super additive in the view of improving the behavior of Si for making suitable new generation anodes for batteries. RGO was varied in the range of 0.1 to 0.5 wt% in the Si matrix. Si/RGO composites were prepared by high energy dry planetary ball milling route. Micro Raman analysis shows the peaks of Si with different Raman shift peaks for carbon (C) such as D, G, and 2D. The purity of the composite was confirmed from energy dispersive spectra (EDS) analysis showing only peaks of Si and C. X-ray photoelectron spectroscopy (XPS), high-resolution transmission electron microscope (HRTEM) and selected area electron diffraction (SAED) results further confirm the successful formation of Si/RGO composites. In the case of the Si/RGO (0.5 wt%) composite, peaks due to Si-C, Si, and C-C were observed by XPS spectra. Interestingly it was observed that RGO reinforcement enhanced the specific surface area and electrical conductivity of the Si matrix. 0.5 wt% reinforced RGO enhanced the specific surface area of Si from 97 to 192 m2 g-1. Si/RGO (0.5 wt%) composite exhibited nearly 8 times more electrical conductivity of 32.06 x 104 Sm-1 in comparison to that of pure Si of 4 x 104 Sm-1.