Hydrothermal Synthesis of Mesoporous Urchin-like Co-Ni-Fe Ternary Hydroxide Nanoneedles on Ni Foam for Electrochemical Applications

A novel mesoporous urchin-like Co-Ni-Fe ternary hydroxide (CoNiFe-TH) assembled by a large amount of nanoneedles on nickel foam was successfully prepared through a facile one-step hydrothermal method. The mesoporous urchin-like CoNiFe-TH nanoneedle electrode has a high specific capacitance of 1318.52 F g(-1) at a current density of 1 A g(-1) in a three-electrode system. Besides, the electrode exhibits an excellent cycling stability with 63.3 % specific capacitance retention and almost 100 % Coulombic efficiency during 1000 cycles of a charge-discharge process at a current density of 5 A g(-1). The excellent electrochemical performance of the electrode is due to the unique mesoporous urchin-like CoNiFe-TH nanoneedles structures with more active reaction sites and polymetallic synergistic effects, which can facilitate the faradic reaction process to improve the electrochemical performance. The current synthesis method can be used for the preparation of other ternary transition metal hydroxides as electrode materials for supercapacitors.