Under mild conditions (near-neutral aqueous solutions, room temperature, and atmospheric pressure), an attractive electrolyte was expanded for splitting water and three novel oxygen-evolution catalysts (Co-C-i, Ni-C-i, Ag-C-i) were generated. The Co-C-i catalyst showed a high oxygen-evolution rate (24.42 mu mol h(-1)), a low oxygen-evolution overpotential (395 mV) and excellent stability. In addition, the non-amorphous Ag-C-i catalyst, different from reported catalyst, was generated. The catalyst has been further characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectrometry (EDS), and X-ray photoelectron spectroscopy (XPS). Copyright (C) 2013, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.