A one-dimensional cobalt-based coordination polymer as a cathode material of lithium-ion batteries†
Abstract
For obtaining high-performance lithium-ion batteries, it is important to develop new cathode materials with high capacity. Herein, a one-dimensional coordination polymer [Co(4-DTBPT) (DMF)2(H2O)2] (4-DTBPT) (C10H4O8) (Co-DTBPT) (4-DTBPT = 2,7-di(4H-1,2,4-triazol-4yl)benzo[lmn][3,8] phenanthroline-1,3,6,8-(2H,7H)-tetraone; DMF = dimethylformamide) was synthesized and its electrochemical performance as the cathode material of lithium-ion batteries was first investigated. The Co-DTBPT electrode showed better cycling stability and a specific capacity of 55 mA h g−1 at 50 mA g−1 after 50 cycles, and the coulombic efficiency was close to 100%. The capacity contribution of the Co-DTBPT electrode may be ascribed to the redox reaction of the Co(II) ion and the 4-DTBPT ligand in the process of charge and discharge. Our work proves once again that using one-dimensional coordination polymers as cathode materials for lithium-ion batteries is a feasible way.