A cylindrical FePO4/MWCNTs composite with a 3D conductive network structure used as a cathode material for lithium-ion batteries

FePO4/MWCNTs (multi-wall carbon nanotubes) composite with a cylindrical core-shell 3D conductive network structure has been fabricated by a simple micro-emulsion technique. Results indicate that FePO4 nanoparticles with a diameter of 10–20 nm are loaded onto the surfaces of MWCNTs, forming a cylindrical core-shell 3D conductive network structure of FePO4/MWCNTs composite. The micro-emulsion plays two key roles in the synthetic process: firstly, dispersing the MWCNTs uniformly, attributing to the presence of an oil phase in the micro-emulsion system; secondly, synthesizing nanoparticle-sized FePO4 due to the nano-sized water nuclear in the micro-emulsion system, decreasing the aggregation of nano-sized FePO4 particles. The FePO4/MWCNTs composite shows excellent electrochemical performance with high discharge capacity, excellent reversibility, and cycling stability. •The cylindrical FePO4/MCNTs core-shell composite is synthesized by a micro-emulsion method.•The micro-emulsion uses to disperse the MCNTs and synthesize nano-sized FePO4.•The FePO4/MCNTs composite cathode exhibits high specific capacity and cycling performance.•The 3D conductive network enhances the high rate performance of the FePO4/MCNTs cathode.