Ultrafine Cobalt Phosphide Nanoparticles Embedded in Nitrogen-Doped Carbon Matrix as a Superior Anode Material for Lithium Ion Batteries

Abstract Ultrafine CoP nanoparticles embedded in nitrogen‐doped carbon matrix derived from zeolitic imidazolate framework 67 (ZIF‐67) template are first obtained. The synthesis strategy only involves a facile method in which ZIF‐67 precursor is phosphided under argon atmosphere. Such novel nanostructure consists of ultrafine CoP nanoparticles and N‐doped carbon matrix which greatly shorten the transport length of lithium ions, effectively buffer the volume expansion during the lithiation/delithiation process, and improve the electrical conductivity. Owing to their unique architecture characteristics, the active material exhibits a superior specific capacity of 522.6 mAh g −1 after 750 cycles at a current density of 200 mA g −1 and outstanding cycling stability up to 2000 cycles at a high current density of 500 mA g −1 . In addition, the active material exhibits superior rate capability.