In situ removal of template to synthesize mesoporous NiCo2O4 for high performance battery-type electrode

In this work, mesoporous NiCo2O4 has been successfully synthesized by in situ removal of template method. The NiCo2O4 composite was precipitated by hydrolysis method using ethylene glycol as a high boiling point solvent at 140 degrees C under atmospheric environment. Zinc hydroxide is used as the sacrificial template to construct the mesoporous structure with high specific surface area. The structure and morphology characteristics were carried out by X-ray diffraction, scanning electron microscopy, high resolution transmission electron microscopy, and N-2 adsorption experiments. The electrochemical properties were investigated through AC impedance spectroscopy, cycling voltammetry and charge/discharge test in 7 M KOH. The results exhibit that the as-prepared mesoporous NiCo2O4 shows a large specific surface area of 219.2 m(2) g(-1), a high specific capacity of 660.53 C g(-1) at current density of 1 A g(-1). The mesoporous NiCo2O4 electrodes still remain 90% specific capacity retention compared with the first cycle over 32,000 cycles, which exhibits the as-prepared electrode possess long-term stability. (C) 2016 Elsevier B.V. All rights reserved.