Li4Ti5O12/graphene nanoribbons composite as anodes for lithium ion batteries

• Published in: SpringerPlus 2015-10, Vol.4 (1), p.643-643, Article 643
• Main Authors: Medina, P. A., Zheng, H., Fahlman, B. D., Annamalai, P., Swartbooi, A., le Roux, L., Mathe, M. K.
• Format: Article
• Language: English
• Subjects: Chemistry and Materials Science; Humanities and Social Sciences; multidisciplinary; Science; Science (multidisciplinary)
• ISSN: 2193-1801; 2193-1801
• DOI: 10.1186/s40064-015-1438-0

In this paper, we report the synthesis of a Li 4 Ti 5 O 12 /Graphene Nanoribbons (LTO/GNRs) composite using a solid-coating method. Electron microscope images of the LTO/GNRs composite have shown that LTO particles were wrapped around graphene nanoribbons. The introduction of GNRs was observed to have significantly improved the rate performance of LTO/GNTs. The specific capacities determined of the obtained composite at rates of 0.2, 0.5, 1, 2, and 5 C are 206.5, 200.9, 188, 178.1 and 142.3 mAh·g −1 , respectively. This is significantly higher than those of pure LTO (169.1, 160, 150, 106 and 71.1 mAh·g −1 , respectively) especially at high rate (2 and 5 C). The LTO/GNRs also shows better cycling stability at high rates. Enhanced conductivity of LTO/GNRs contributed from the GNR frameworks accelerated the kinetics of lithium intercalation/deintercalation in LIBs that also leads to excellent rate capacity of LTO/GNRs. This is attributed to its lower charge-transfer resistance (Rct = 23.38 Ω) compared with LTO (108.05 Ω), and higher exchange current density (j = 1.1 × 10 −3 mA cm −2 )—about 20 times than those of the LTO (j = 2.38 × 10 −4 mA cm −2 ).