LiV3O8 and Graphene Oxide Nanocomposite as a Cathode in Lithium-Ion Batteries

In this work, a LiV3O8/GO nanocomposite (N1-LVO/GO) was fabricated through a one-step hydrothermal process followed by postsintering treatment as well as a wet-chemistry method. When utilized as an active cathode for lithium-ion batteries (LIBs), N1-LVO/GO delivers the specific capacities of 366.1 mAh/g in the initial reversible cycle, 230.8 mAh/g in the 50th cycle, and 210.4 mAh/g in the 100th cycle at 100 mA/g between 1.5 and 4 V (vs Li/Li+). Even under 1200 mA/g, its capacity can be maintained at 148.6 mAh/g. N1-LVO/GO exhibits better Li+ storage performance compared to its counterpart without the introduction of GO (N1-LVO) and other LiV3O8 samples (M-LVO obtained by direct solid-phase sintering and N2-LVO prepared by a two-step wet-chemistry method in combination with postsintering). For one thing, the superior Li+ storage properties of N1-LVO/GO can be ascribed to its smaller size at the nanoscale deriving from the cracking reaction during postsintering, which offers more active sites for Li+. For another, the introduction of GO by uniform recombination with N1-LVO via CTAB under wet-chemistry conditions not only prevents the reunion of the N1-LVO nanomonomer but also serves as strain buffer upon Li+ insertion/extraction within N1-LVO. So, it will make full use of the active cathode and simultaneously avail its cyclic stability. This N1-LVO/GO could be adopted as a promising cathode for future LIBs with high performance.