α-LiFeO
2 columnar particles were synthesized by heating a mixture of γ-Fe
2O
3 and LiNO
3 at 500°C in air. CeO
2 nanoparticles were prepared from Ce(OH)
3 obtained by a precipitation method. The α-LiFeO
2 columnar particles were mixed with the CeO
2 nanoparticles in an aqueous solution and then the mixture of α-LiFeO
2 and CeO
2 was heated at 300°C to prepare the α-LiFeO
2 coated with CeO
2 nanoparticles. Then the effect of CeO
2 coating on CO
2 absorption ability of α-LiFeO
2 was investigated. As a result, coating of CeO
2 on α-LiFeO
2 particles was found to suppress the structural phase transition of α-LiFeO
2 to β′-LiFeO
2, although the synthesized α-LiFeO
2 underwent a structural phase transition of α-LiFeO
2 to β′-LiFeO
2 accompanied by the reaction of α-LiFeO
2 with CO
2 in the temperature range of 350 to 425°C. The suppression of the structural phase transition resulted in an increase in CO
2 absorption rate of LiFeO
2 in the temperature range up to 425°C. Thermodynamic analysis revealed that the α-LiFeO
2 phase has a lower activation energy for CO
2 diffusion than the β′-LiFeO
2 phase, which results in the enhancement of the CO
2 absorption rate of LiFeO
2.
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