Studies on redox H2–CO2 cycle on CoCrxFe2−xO4

Abstract Completely reduced CoCr x Fe 2 − x O 4 can be used to decompose CO 2 . It was found that for pure CoFe 2 O 4 there is no FeO formation in the first step while there is formation in the second step. For CoCr 0.08 Fe 2−0.08 O 4 , there is no FeO formed in all the oxidation process, because of effect of Cr 3+ . Pure CoFe 2 O 4 was destroyed at the first reaction cycle of H 2 reduction and CO 2 oxidation, while doped Cr 3+ spinel CoCr 0.08 Fe 1.92 O 4 showed good stability. The results from H 2 -TG, CO 2 -TG and XRD show that the addition of Cr 3+ to CoFe 2 O 4 can inhibit the increasing of crystallite size and the sintering of alloy. Most importantly, the CoCr 0.08 Fe 1.92 O 4 can be used to decompose CO 2 repeatedly, implying that it is a potential catalyst for dealing with the CO 2 as a ‘green house effect’ gas.