A high N content cobalt-based metal organic framework with nanorod structure for supercapacitor electrode material

A high N content supercapacitor electrode material, cobalt-based metal organic framework (named as Co-MOF) with a structure of nanorod, is prepared by solvothermal method. The synthesis temperature and feed ratio are optimized (140 °C, 1:2 M ratio of Co to the ligand) to achieve 414.5 F g−1 specific capacitance at a current density of 0.5 A g−1 in 3 M KOH. The prepared electrode in two-electrode test also delivers a specific capacitance of 334.4 F g−1 at 0.5 A g−1 with an energy density 12.0 Wh kg−1 at the power density of 258.1 W kg−1. More significantly, the capacitance retention rate is up to 113% after 20,000 cycles at a current density of 10 A g−1, which can be attributed to the electrochemical activation process.