Facile approach to prepare hollow core-shell NiO microspherers for supercapacitor electrodes

A facile lamellar template method (see image) has been developed for the preparation of uniform hollow core-shell structure NiO (HCS-NiO) with a nanoarchitectured wall structure. The prepared NiO was found to be highly crystalline in uniform microstructures with high specific surface area and pore volume. The results indicated that ethanol interacted with trisodium citrate played an important role for the formation of hollow core-shell spheres. On the basis of the analysis of the composition and the morphology, a possible formation mechanism was investigated. NiO microspheres with hollow core-shell showed excellent capacitive properties. The exceptional cyclic, structural and electrochemical stability with similar to 95% coulombic efficiency, and very low ESR value from impedance measurements promised good utility value of hollow core-shell NiO material in fabricating a wide range of high-performance electrochemical supercapacitors. (c) 2013 Elsevier Inc. All rights reserved.