1. Introduction
Lithium ion batteries (LIBs) have become one of the most
successful commercialized energy storage devices [1–3]. The
growing demands for high energy/power applications have
encouraged great research efforts to develop cost-effective and
high-performance electrode materials for LIBs [4–7]. However,
current commercial graphite based anodes have a relatively low
theoretical capacity of
372 mAh g1, which is far below largescale
energy applications. Thus, it is highly critical to explore
alternative anode materials that could endow LIBs with both
higher energy density and better rate performance. Cobalt oxide
based materials have attracted great attention as promising anode
materials [8,9]. Particularly, Co3O4 can theoretically deliver as high
as three times the capacity of graphite due to its 8-electron transfer
reaction upon cycling [10]. However, the poor ionic and electronic
conductivity of Co3O4 electrodes results in slow reaction kinetics
and insufficient Li storage performance [11], especially at high
discharge/charge rates requiring fast ion/electron transportation.
There has been a variety of reports of preparing different Co3O4
nanostructures for LIBs application. [12–15] According to the
published electrode configurations, these works can be classified
into two basic types: (i) binder-enriched [16] and (ii) binder-free