Synthesis of Co_1&minus;<i>_x</i>Fe<i>_x</i> Hydroxide Nanoplatelets and Its Electrochemical Performances as Supercapacitor Electrode Materials

Abstract

Co-Fe layered double hydroxides (Co 1−x Fe x LDHs) were synthesized by a chemical co-precipitation method. It was found that the molor ratio of Co to Fe had a significant effect on the electrochemical activity. The specific capacitance of 869 F g −1 was achieved when the molor ratio of Co to Fe was equal to 0.74:0.26. The Co 0.74 Fe 0.26 LDH sample had a BET specific surface area of 202.9 m 2 g −1 and total pore volume of 0.6 cm 3 g −1, which led to the high liquid-solid interfacial area and further increased the utilization of the active materials. Additionally, the Co 0.74 Fe 0.26 LDH electrode exhibited a good electrochemical stability with beyond 99.5% of the initial capacitance over 1000 consecutive cycles at 1 A g −1. It is a promising electrode material for supercapacitor.