Pomegranate-like CoO@nitrogen-doped carbon microspheres with outstanding rate behavior and stability for lithium storage†
Abstract
The rational design and preparation of CoO-based materials with excellent electrochemical performances for lithium ion batteries (LIBs) are highly desirable. In this work, we develop a CoO-based material with a novel pomegranate-like microspherical structure, in which ultrafine CoO nanoparticles coupled with a carbon framework are intimately confined within N-doped carbon outer shells (denoted as CoO@NC). Such a robust pomegranate-like architecture can not only facilitate the electron/mass transport in CoO/carbon electrodes to boost rate capability, but can also minimize aggregation of CoO microstructures to prolong their cycle life during the electrochemical process. Correspondingly, the CoO@NC nanocomposite manifests a high capacity of around 1200 mA h gā1 at 0.1C, excellent cycling stability up to 150 cycles, and a superior rate capability of 533 mA h gā1 at 10C as an anode material for LIBs.