不同表面活性剂对La_2Ce_2O_7纳米晶体生长活化能的影响

Influence of Different Surfactants on the Activation Energy of Crystal Growth for La_2Ce_2O_7 Nanocrystalline

以La_2O_3和Ce(NO_3)_3·6H_2O为原材料,以SDBS和CTAB为表面活性剂,采用水热合成法制备了La_2Ce_2O_7纳米晶体。通过XRD、Raman、SEM和TEM对粉体的物化性能进行了分析,讨论了不同表面活性剂对晶体生长活化能的影响。结果表明:添加两种表面活性剂的样品均为萤石结构,以CTAB为表面活性剂的样品晶粒尺寸为11.4 nm,比表面积为187.53 m^2·g^(-1),其晶体生长活化能(16.33±0.02 k J·mol^(-1))要大于添加阴离子表面活性剂(SDBS)的样品(13.47±0.03 k J·mol^(-1))。

La2Ce2O7 nanocrystallines were prepared by hydrothermal method with La2O3 and Ce （NO3） 3 6H2O as precursors, SDBS and CTAB as surfaetants. The physicoehemieal performance of the products were investigated by XRD, Raman, SEM and TEM. The influence of different surfactants on the activation energy of crystal growth was also discussed. Qualitative analyses indicate that the sample with CTAB as surfactant shows cubic fluorite structure, the specific surface area and the average crystallite size are 187.53 m2 g-1 and 11.4 nm, respectively. In addition, the activation energy of crystal growth of CTAB （ 16.33 ±0.02 kJ mol-1 ） is higher than that of SDBS （ 13.47 ±0.03 kJ mol-1 ）.