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Highlights: [•] Cookies-shaped LiV3O8 material was synthesized by a facile sol–gel method. [•] The compound shows high capacity retentions at different current densities. [•] The good performance is due to high crystallinity and little dissolution of vanadium. [ABSTRACT FROM AUTHOR]

Abstract: Porous Fe3O4/C core/shell nanorods have been prepared by a facile hydrothermal method using porous Fe2O3 nanorods as the precursor and glucose as the carbon source. The Fe3O4/C nanorods possess a uniform size with 50–80nm in diameter and 300–500nm in length, and are homogenously coated by amorphous carbon layer. The porous nanorods greatly increase the electrical contact, thus facilitating the Li-ion and electron transportation, and enhancing the reactivity of the electrode. Also, the carbon layer can effectively limit the volume expansion and detachment of Fe3O4, and thus increase its structure stability during cycling. In the context of lithium storage behavior, the Fe3O4/C nanorod electrode shows high capacity and good cycle stability, as well as enhanced rate performance. After 50 cycles, the reversible capacity of the porous Fe3O4/C nanorods is 762.1mAhg−1 at 0.1C and 597.2mAhg−1 at 0.5C, much higher than that of α-Fe2O3 nanorods (276.4mAhg−1) and Fe3O4 nanoparticles (307.9mAhg−1). At a high rate of 1C, the specific capacity of Fe3O4/C nanorods is still as high as 630.1mAhg−1. [Copyright &y& Elsevier]

Abstract: The multi-walled carbon nanotubes (MWCNTs) modified Li3V2(PO4)3/C composite is synthesized by polyvinyl alcohol (PVA) based carbon-thermal reduction method using MWCNTs as a highly conductive agent. PVA mainly supplies a reductive atmosphere to reduce V5+ and provides a network of carbon to inhibit the aggregation of Li3V2(PO4)3 particles. The amorphous carbon coating and MWCNTs co-modified composite shows excellent high-rate lithium intercalation/deintercalation property and cycling performance between 3.0 and 4.3V. The discharge capacities of 131.7 and 122.9mAhg−1 are obtained at rates of 1C and 10C, respectively, for the Li3V2(PO4)3/(C+MWCNTs). These improvements are attributed to the valid conducting networks of C+MWCNTs and the reduced Li3V2(PO4)3 particle size by the network carbon from the pyrolysis of PVA. [Copyright &y& Elsevier]