Decomposition of CO2 to Carbon Using Oxygen-Deficient Zn(II)-Bearing Ferrite

Abstract

AbstractOxygen-deficient Zn(II)-bearing ferrites (ZnxFe3-xO4-δ, 0≤×≤l, δ>0) have been synthesized and studied for their reactivity in the decomposition of CO2 to carbon at 300 °C. They were prepared by reducing Zn(II)-bearing ferrites with H2 gas at 300 °C. The oxygen-deficient Zn(II)-bearing ferrites consisted of a single phase of a spinel-type structure which was oxygendeficient compared with their stoichiometric compositions. Their lattice constants were larger than those of the corresponding stoichiometric spinels. Decomposition of CO2 to carbon proceeded accompanied by an oxidation of the oxygen-deficient Zn(II)-bearing ferrite. The amount of carbon deposited on the ferrite decreased when Zn content in Zn(II)-bearing ferrite increased. The decrease in the amount of carbon deposited is due to changes in the electron conductivity according to the Zn content in Zn(II)-bearing ferrite. These changes contribute to their reactivity for decomposition of CO2 to carbon.