Electrochemical Performance of Iron Diphosphide/Carbon Tube Nanohybrids in Lithium-ion Batteries

•Dehydrogenated FeP2/C nanohybrids were fabricated via a facile annealing process.•The nanohybrids as anode in LIB show excellent cycling stability and rate capability.•C-hybrid promotes buffering volume change and increasing electroconductibility.•The process can be applied for the fabrication of many more TMPs and nanohybrids.

Phosphorous-rich phase iron diphosphide/carbon tube (FeP2/C) nanohybrids, which are synthesized via a pyrolysis process and composed of heterostructures of orthorhombic FeP2 with conical carbon tubes, have been identified as a new anode in lithium-ion batteries. After an annealing treatment to eliminate the excessive hydrogen elements in the carbon tubes, the FeP2/C nanohybrids display good reversible capacity, long cycle life, and excellent rate capability. Specifically, the annealed hybrids exhibit a discharge capacity of 602 mA h g−1 on the second cycle and a discharge capacity of 435 mA h g−1 after 100 cycles at 0.1C (0.137 A g−1). Meanwhile, these annealed hybrids exhibit excellent rate capability, such as a reversible capability of 510 mA h g−1, 440 mA h g−1, 380 mA h g−1, 330 mA h g−1 and 240 mA h g−1 at 0.25C, 0.5C, 1C, 2.5C and 5C, respectively.

Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slide