Binder Free Mesoporous Spinel Oxides As an Anode Materials for High Performance Li-Ion Battery

Abstract

The development of anode material with high specific capacity is the key issue in present lithium ion batteries (LIBs) technology. Recently, transition metal oxides (TMOs), especially cobalt-based oxides with spinel structure have attracted much attention as an anode material for LIBs due to its high theoretical capacity (~700 mAh g-1), long cycle life and high rate performances. In view of the high cost of Co, ternary cobalt oxides via partially substituting Co with less expensive metals, such as Cu, Zn, Ni, Fe, Ni, and Mn, are more practical anode materials for applications. Among these Cu and Zn not only less expensive, but also electrochemically active and contributes to the charge storage. Nevertheless, operation stability and high rating performance are two critical issues needing improvement before wide application of MCo2O4 (M=Cu, Zn) can be realized. However, the limitations of TMO materials could be possibly overcome by tailoring morphology and pore size distribution to sustain structural disintegration during cycling and promote lithium ion storage. Herein, flower-like and microsphere MCo2O4 (M=Cu, Zn) were synthesized by hydrothermal strategy with porous structure. A facile urea-assisted hydrothermal method and subsequent calcination for 2 h was pursued to obtain pure flower-like and microsphere MCo2O4 (M=Cu, Zn) samples. The Ni-foam was used as substrate for in-situ deposition MCo2O4 (M=Cu, Zn). The obtained flower-like and microspheres morphology was assembled by nanorods, and the nanorods were comprised of interconnected particles with a porous structure. The important properties of electrode material such as morphology, size, surface area, porosity, pore size distribution highly desirable for its high performance. The desirable electrochemical performance of MCo2O4 (M=Cu, Zn) clearly indicates it is promising candidates as an anode material for LIB. This work was supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Education (Grant number: NRF-2013R1A1A2060638 and No. 2009-0093816).