乙二醇对反向微乳辐照法制备纳米级氧化亚铜形貌的影响

The Effect of Ethylene Glycol on the Morphology of Cu_2O Nanoparticles Synthesized in W/O Microemulsion by γ-Irradiation

在乙二醇存在下,采用反向微乳辐照法制备了纳米级氧化亚铜(Cu2O)立方体。利用吸收光谱、X射线粉末衍射(XRD)、透射电镜(TEM)、高分辨透射电镜(HRTEM)、扫描电镜(SEM)等对所得产物进行了表征。吸收光谱显示随着乙二醇用量逐渐增加,Cu2O的半导体激子吸收特征峰逐渐增强并且红移,初步表明所得产物的粒径逐渐增大。常规透射电镜的结果表明所得Cu2O的纳米颗粒的粒径逐渐增大,并且变得规整。实验结果表明,乙二醇对Cu2O纳米粒子的形貌具有重要影响。乙二醇的存在增大了微乳水池粘度,而粘度大小影响水化电子的反应性,从而影响Cu2O的生成速率、结晶过程。它还可以降低微乳界面刚性,增大水池间的物质交换而影响Cu2O的成核和结晶;此外,它对Cu2O特定晶面的吸附影响其最终形貌。

Cuprous oxide nanocubes were successfully prepared in w/o microemulsions by γ-irradiation in the presence of ethylene glycol （EG）. Absorption spectrum, XRD, TEM, HRTEM and SEM were used to characterize the as-prepared nanoparticles. The characteristic peak of Cu2O of absorption spectra of the irradiated microemulsions red-shifts apparently with the EG increasing, showing that the as-prepared Cu2O particle size becomes larger. TEM images verify this point and indicate that Cu2O nanoparticles become uniform with the increase of EG. The results indicated that EG played an important role in the structures of cu- prous oxide nanoprticles. Firstly, EG increased the viscosity of water-pools of microemulsions which affected the reactivity of hydrated electrons and finally influenced the reduction of Cu2＋ and the precipitation of Cu2O. Secondly, EG reduced the rigidity of the interface of microemulsions and enhanced the mass exchange among water pools which impacted the nucleation and precipitation of Cu2O. Thirdly, EG adsorbed certain crystal faces of Cu2O and influenced the final morphology of Cu2O.