Synthesis of Cobalt Ion-Based Coordination Polymer Nanowires and Their Conversion into Porous Co3O4 Nanowires with Good Lithium Storage Properties

Cobalt ion-based coordination polymer nanowires were synthesized by using nitrilotriacetic acid (NA) as a chelating agent by a one-step hydrothermal approach. In the synthesis, cobalt ions were bonded with amino or carboxyl groups of NA to form one-dimension polymer nanowires, which can be confirmed by FTIR and TGA results. Our experimental results show that the morphologies of polymer nanowires greatly depend on the precursor salts, ratios between deionized water and isopropyl alcohol. The probable molecular formula and growth mechanism have been proposed. After heat treatment, the cobalt ion-based coordination polymer nanowires can be converted into porous Co3O4 nanowires, which completely preserved the nanowire-like morphology. When used as anodes in lithium-ion batteries, the obtained porous Co3O4 nanowires exhibited a high reversible capacity of 810 mA h g(-1) and stable cyclic retention at 30th cycle. The good electrochemical performance could be attributed to the porous nanostructure of Co3O4, which provides pathways for easy accessibility of electrolytes and fast transportation of lithium ions.