Facile hydrothermal synthesis and characterization of Co2GeO4/r-GO@C ternary nanocomposite as negative electrode for Li-ion batteries

Ternary nanocomposite of Co2GeO4/r-GO@C is synthesized by single step hydrothermal method followed by calcination. The XRD analysis reveals the formation of cubic structured Co2GeO4 and their corresponding functional groups identified through Raman analysis. The TEM analysis assures that uniform distribution of Co2GeO4 nanoparticles on the r-GO layers. The Galvanostatic charge-discharge (GCD) curve demonstrates that the initial discharge capacity of pristine Co2GeO4, Co2GeO4/r-GO and Co2GeO4/r-GO@C composite is 1400, 1284 and 1594 mA h g(-1) at 50 mA g(-1), respectively. The cycling stability curve shows the specific capacity of 609, 970 and 1180 mA h g(-1), for pristine, Co2GeO4/r-GO and Co2GeO4/r-GO@C composite, respectively over 15 cycles. The ternary composite of Co2GeO4/r-GO@C delivers the discharge capacity of 323 mA h g(-1) at high current density of 1 A g(-1) over 500 cycles with capacity retention of 71%. The rate capability curve indicates that Co2GeO4/r-GO@C composite shows the better rate capability. (C) 2017 Elsevier Inc. All rights reserved.