Facile synthesis of SiOx@C composite nanorods as anodes for lithium ion batteries with excellent electrochemical performance

Abstract

To develop high-capacity anode materials for lithium-ion batteries with long cycle life, SiOx@C composite nanorods are fabricated by a template assisted hydrothermal route followed by pyrolysis, using ethyltriethoxysilanes (EtSi(OEt)3), resorcinol/formaldehyde (RF) and cetyltrimethyl ammonium bromide (CTAB) as starting materials. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Raman spectroscopy (RA), X-ray photoelectron spectroscopy (XPS) and elemental analysis (EA) are employed to characterize the morphology, microstructure and composition of the as-prepared composite. The composite shows a rod-like morphology, which is composed of 65.4 wt% SiOx (x = 1.12) and 34.6 wt% C, and individual rod contains numerous interconnected nanospheres. When used as anodes in lithium-ion batteries, the SiOx@C nanorods exhibit a discharge capacity of about 720 mAh g−1 after 350 cycles at a current density of 100 mA g−1. The excellent electrochemical performance is attributed to the enhanced conductivity and unique material structure of the composite.