Fast synthesis and electrochemical performance of hollow NiCo 2 O 4 flowerlike microstructures

In the present work, a two-step route was designed for fast synthesis of hollow NiCo 2 O 4 flowerlike microstructures. A flowerlike precursor containing Ni and Co was firstly prepared via a fast microwave-assisted hydrothermal route. Then, hollow NiCo 2 O 4 flowerlike microstructures were successfully obtained through pyrolyzing the above precursor. Experiments showed that the pyrolysis temperature could strongly affect the performance of the final product. The product prepared at 280 °C exhibited a bigger BET surface area and higher specific capacitance than that prepared at 400 °C. The as-prepared NiCo 2 O 4 microstructures were characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (FESEM), (high resolution) transmission electron microscopy (HRTEM/TEM) and energy dispersive X-ray spectrometry (EDS).