| Abstract: |
Cobalt nickel double hydroxides (CoxNi1–x LDHs) nanoparticles were synthesized by a polyvinyl pyrrolidone-assisted chemical co-precipitation method. It was found that the ratio between Co and Ni had a significant effect on their electrochemical activities. The speci？c capacitance of 2614 F g？1 was achieved when the atomic ratio of Co to Ni was equal to 0.57: 0.43. This Co0.57Ni0.43 LDH sample had a BET specific surface area of 109.8 m2 g-1 and total pore volume of 0.6036 cm3 g？1 , and its pore size distribution was mainly in the range of 1.5-5 nm, which led to the high liquid–solid interfacial area and further increased the utilization of the active materials. Additionally, the Co0.57Ni0.43 LDH electrode exhibited a good electrochemical stability with 86.4% of the initial capacitance over 1,000 consecutive cycles at 5 A g–1.
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