Carbon nanotubes (CNTs) and porous Co3 O4 nanorod (Co3 O4 p-NR) composites are self-assembled to form a hierarchical porous structure through a facile hydrothermal method to meet the requirements of long cycle life, high capacity, and excellent rate capability for next-generation lithium-ion batteries. CNTs are embedded in Co3 O4 p-NR clusters to form a 3D conductivity network, which reduces the transportation resistance of electrons and ions. Co3 O4 p-NRs are assembled from nanoparticles, which enlarge the contact area between electrode and electrolyte to provide more space to buffer the large volumetric changes associated with repeated electrochemical reactions and maintain the structural integrity. The obtained samples exhibit a high reversible capacity (1083 mA h g-1 after 140 cycles at 0.5 Ag-1 ), superior rate capability (521 mA h g-1 at 8 Ag-1 ), and excellent cyclic stability, with a capacity decay of 0.57 mA h g-1 per cycle at a high current of 1 Ag-1 over 200 cycles. The specific heterodimensional structure gives rise to a new approach to exploit high-performance electrode materials.
Keywords: carbon; electrochemistry; mesoporous materials; nanotubes; self-assembly.
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