High-performance lithium storage of Co3O4 achieved by constructing porous nanotube structure

Abstract

Co3O4 has been investigated intensively for its high specific capacity which makes it a promising candidate anode for high-performance lithium ion batteries (LIBs). However, rational design of Co3O4 electrode that is beneficial for its electrochemical performance is still a great challenge. Herein, we designed and fabricated porous Co3O4 nanotubes (P-Co3O4-NTs) by coaxial electrospinning method followed by a fine annealing treatment, which display one dimensional tubular structure with porous wall and hollow interior. The uniqueness of this strategy is that the morphologies of the P-Co3O4-NTs could be tuned by adjusting the mass ratio of reactants. The resultant P-Co3O4-NTs exhibit excellent lithium storage performance in terms of specific capacity, rate capability, and cycling stability, when used as an anode material for rechargeable LIBs. This unique structure endows a high reversible specific capacity of 1826.2mAg−1 at a current density of 0.3Ag−1 after 100 cycles. Even at high current densities of 2 and 5Ag−1, the P-Co3O4-NTs electrode still could deliver remarkable discharge capacities of 1506.2 and 1145.1mAhg−1, respectively. The excellent electrochemical performance can be attributed to the unique tubular and porous structure of P-Co3O4-NTs, which not only can accommodate the large volume change but also can provide an excellent ion diffusion and electronic conduction pathway. Therefore, the P-Co3O4-NTs have the potential for use as a high performance anode material in LIBs.