Pristine Cobalt-based 2D metal organic framework for high performance supercapacitor electrodes

2D metal organic frameworks (MOFs) have attracted a significant interest for their applications in energy storage devices. Herein, we report a scalable and low-cost approach for the fabrication of pristine Cobalt-based 2D metal organic framework Co-HAB electrodes using electrophoretic deposition (EPD). We used two different preparations for the Co-HAB solution used in EPD. The morphology of the electrophoretically deposited Co-HAB on Nickel foams characterized by SEM and TEM revealed nanosheets and abundant in-plane pores for both preparations. The resulting symmetric Co-HAB supercapacitors in Na₂SO₄ electrolyte, exhibited excellent electrochemical capacitive performance over a wide cell potential window of 0.0-1.2V. Operating at ultra-high charge-discharge rates, up to 4000mVs^-1, the Co-HAB supercapacitors delivered an excellent areal specific capacitance of 46.3 mFcm^-2. The Co-HAB prepared with the addition of dimethylformamide (DMF) showed a higher areal capacitance, of about twice the areal capacitance obtained for the solution without DMF. Furthermore, the Co-HAB supercapacitors exhibited high cycling stability with a retention of about 98% over 10,000 cycles.