Formation of hollow Co₃O₄ nanocages with hierarchical shell structure as anode materials for lithium-ion batteries

Abstract

Two kinds of unusually hollow and porous Co₃O₄ nanocages with high complexity in shell architecture and high surface areas of 58.8 and 43.8 m² g⁻¹ are synthesized by a straightforward pyrolysis of zeolitic imidazolate framework (ZIF-67) rhombic dodecahedrons as self-sacrificing template under different temperature. The two types complex hollow Co₃O₄ nanocomposites utilized as anode materials for Lithium ion batteries (LIBs) manifested the initial discharge capacities as high as 2169 and 1928 mA h g⁻¹ and initial Coulombic efficiency under a specific current of 100 mA g⁻¹, which could still show a high reversible capacity of 915 and 668 mA h g⁻¹ after 100 cycles. The two electrodes materials also exhibited rate capability of 322 and 169 mA h g⁻¹ at a large specific current of 2 A g⁻¹. The hollow architecture, complex shell structure, high surface area and ultrafine building blocks might give rise to the high specific capacities. Moreover, the simple synthesis route rendered it to be a potential and promising electrode materials for rechargeable LIBs.