Mesoporous ZnCo₂O₄ microspheres composed of ultrathin nanosheets cross-linked with metallic NiSi_x nanowires on Ni foam as anodes for lithium ion batteries

ZnCo₂O₄ microspheres with hierarchical mesoporous structures composed of ultrathin nanosheets cross-linked with metallic NiSi_x nanowires are successfully synthesized on Ni foam via a combined facile chemical vapor deposition (CVD) and simple but powerful chemical bath deposition (CBD) followed by a calcination process. The ZnCo₂O₄ microspheres/NiSi_x nanowires are directly employed as binder- and conductive-agent-free anodes for lithium ion batteries (LIBs). The resultant integrated electrodes exhibit remarkable electrochemical performances in terms of high specific capacity, superior rate capability and outstanding cycling stability due to their advantageously structural features including mesoporous feature of ZnCo₂O₄ microspheres, highly conductive NiSi_x nanowire scaffold and cross-linked network structure with the intimate interconnection between ZnCo₂O₄ microspheres and NiSi_x nanowires. A reversible capacity up to 701mAhg^-1 after 340 cycles at a high current density of 1Ag^-1 and a capacity of about 373mAhg^-1 after 10 cycles even at a current density as high as 4Ag^-1 can be retained, suggesting their great potential as efficient electrodes for high-performance LIBs.