A carbon-bearing nickel(II) ferrite: a tailor-made solid reactant for two-step thermochemical water splitting at 300 °C

Abstract

Carbon-bearing nickel(II) fernte (CBNF) was prepared by repeated decomposition of CO₂ on H₂-reduced nickel(II) ferrite, and was used in a two-step thermochemical water splitting at 300 °C Gaseous hydrogen could be generated efficiently by the decomposition of water molecules via the redox pair CBNF*/H₂O, (CBNF* denotes activated CBNF). The noble material was also characterized by Mössbauer spectroscopy, X-ray diffraction (XRD) and chemical analysis. A peculiar amorphous surface layer composed of carbon, divalent transition metals and oxide ions (CIO layer) was inferred to be responsible for the water-splitting reactivity