Tb掺杂DyBaCo4O7+δ纳米粉体的制备及其氧吸附/脱附性能的研究.

Rare earth element Tb doped DyBaCo4O7+δ nano-powder was synthesized by sol-gel process.The effect of Tb doping with different concentration on the morphology, crystal structure and oxygen adsorption-desorption properties of DyBaCo4O7+δnano-powder was studied.Dy1-xTbxBaCo4O7+δ nanopowder is still hexagonal close packed crystal structure at low Tb doping concentration. Tb doping has little effect on the morphology of Dy1-xTbxBaCo4O7+δnanopowder. From room temperature to 1 000 ℃, DyBaCo4O7+δnanopowder and Dy1-xTbxBaCo4O7+δnanopowders showed two times of oxygen adsorption and desorption.Compared with the oxygen adsorption performance of DyBaCo4O7+δnanopowder, the oxygen adsorption capacity of Tb doped DyBaCo4O7+δ nanopowder is obviously higher than that of undoped DyBaCo4O7+δ. The oxygen adsorption capacity of DyBaCo4O7+δis 1.4%, while the oxygen adsorption capacity of Dy1-xTbxBaCo4O7+δis 4.9%. DyBaCo4O7+δnanopowders and Dy1-xTbxBaCo4O7+δnanopowders showed good oxygen adsorption/desorption behavior during N2/O2 gas switching. The improvement of the oxygen adsorption/desorption performance of DyBaCo4O7+δcan be attributed to the improvement of the spacing of DyBaCo4O7+δand the increase of the oxygen storage space of DyBaCo4O7+δ. [ABSTRACT FROM AUTHOR]