Three-Dimensional Polypyrrole Nano-Network with Sb Nanocrystals as Electrode Material for Sodium-Ion and Lithium-Ion Batteries

In this work, we develop an approach to synthesize a nanoscale structure with Sb nanocrystals and polypyrrole nano-network (Sb@ppy NNW) from the reduction of SbCl₃ and the polymerization and crosslinking of pyrrole. The Sb@ppy NNW exhibits excellent electrochemical characteristics with incessant conduction paths for fast transfer of electrons, short paths for fast diffusion/migration of ions and large contact area between active material and electrolyte for the storage of Na/Li. The Sb@ppy NNW is used as active material in the working electrode for lithium-ion half cells and sodium-ion half cells. The sodium-ion half cells possess excellent cycling stability with a high specific capacity of 510 mA h g^-1 at a current density of 100 mA g^-1 and 463 mA h g^-1 after 100 cycles at a current density of 500 mA g^-1, and superior rate performance with a specific capacity of 635.6 mA h g^-1 even at a current density of 1600 mA g^-1. The specific capacities for the lithium-ion half cells are 660 mA h g^-1 after 100 cycles at a current density of 100 mA g^-1 and 635.6