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以(CH_2OH)2和H_2O的混合溶液为溶剂,Ce(NO_3)_3?6H_2O和In(NO_3)_3?4.5H_2O分别为Ce和In源,采用溶剂热法在200℃下合成了前驱体,再经500℃焙烧2 h制备了In~(3+)掺杂的CeO_2粉末.通过研究一系列In~(3+)的添加浓度,得出In~(3+)掺杂CeO_2中In~(3+)的固溶度为1%(摩尔分数).In~(3+)掺杂对CeO_2形貌的影响不大,固溶In~(3+)前后的CeO_2颗粒形貌均为层状结构,但当In~(3+)的添加量高于固溶度时,出现了细碎的第二相颗粒.In~(3+)饱和掺杂浓度时CeO_2粉末的比表面积高于未掺杂的CeO_2,达到100 m2/g,当In~(3+)的添加量大于等于3%时比表面积有所下降.In~(3+)添加量对储氧能力的影响为:首先,In~(3+)的引入能够明显降低CeO_2的低温还原峰温度;其次,当In~(3+)的添加量为饱和浓度1%时,CeO_2的低温储氧能力由未掺杂的3.6×10-4mol/g提高到4.4×10-4mol/g;当In~(3+)的浓度大于等于3%时,试样的低温储氧能力先有所下降,随后趋于稳定.不同In~(3+)添加量CeO_2粉末的晶格常数、氧空位浓度、比表面积和低温储氧能力都在1%In~(3+)固溶度的位置出现了转折.低温储氧能力与比表面积和氧空位浓度都有关联,是二者综合作用的结果.
Ce (NO_3) _3 · 6H_2O and In (NO_3) _3 · 4.5H_2O were used as the precursors of Ce and In respectively by the mixed solution of (CH 2 OH) 2 and H_2O. The precursor was synthesized by solvothermal method at 200 ℃. In ~ (3+) doped CeO 2 powders were prepared by calcination at 500 ℃ for 2 h. By studying a series of In 3+ concentration, +) Has a solid solubility of 1% (mole fraction) .In ~ (3+) doping has little effect on the morphology of CeO_2, the morphology of CeO_2 particles before and after solid solution In ~ (3+) , But the fine second phase particles appeared when the content of In 3+ was higher than the solid solubility.The specific surface area of CeO 2 powder was higher than that of undoped CeO 2, reaching 100 m2 / g, and the specific surface area decreased when In 3+ was more than 3% .The effect of In 3+ on oxygen storage capacity was as follows: Firstly, 3+) can significantly decrease the temperature of the reduction peak of CeO_2. Secondly, when the concentration of In 3+ is 1% of the saturation concentration, the low oxygen storage capacity of CeO 2 is controlled by the amount of undoped 3.6 × 10-4 mol / g increased to 4.4 × 10-4mol / g, and when the concentration of In 3+ was greater than or equal to 3%, the oxygen storage capacity of the sample first decreased and then stabilized. The lattice constants, oxygen vacancy concentration, specific surface area and oxygen storage capacity of CeO_2 powder with the addition amount of In ~ (3+) all turned around at 1% In 3+ solid solubility. And the specific surface area and oxygen vacancy concentration are related, is the result of the combined effect of the two.