Amorphous red phosphorus anchored on carbon nanotubes as high performance electrodes for lithium ion batteries

Abstract

Red phosphorus-carbon nanotube (P@CNT) composites were synthesized as anodes for advanced lithium ion batteries via a facile solution-based method at room temperature. In these composites, the entangled P@CNT nanostructure reduced the aggregation of both components and allowed their complete utilization in a synergetic manner. The highly conductive and porous CNT framework, along with the nanoscale red P particles intimately anchored on the CNT surface, conferred the composite with excellent ion/electron transport properties. Volume expansion within the red P particles was mitigated by their amorphous and nanoscale features, which can be well buffered by the soft CNTs, therefore maintaining an integrated electrode structure during cycling. When used as an anode in lithium ion batteries, the composite exhibited a reversible capacity of 960 mAh·g−1 (based on the overall weight of the composite) after 120 cycles at 200 mA·g−1. The composite also delivered excellent high-rate capability with capacities of 886, 847, and 784 mAh·g−1 at current densities of 2,000, 4,000, and 10,000 mA·g−1, respectively, which reveals its potential as a high performance anode for lithium ion batteries.