纳米氧化锌包覆SiO_2和SiO_2/Al_2O_3改性粉制备及表征

Preparation and characterization of ZnO nanoparticles coated and modified by SiO_2 and SiO_2/Al_2O_3

采用液相沉积法对纳米氧化锌进行表面包覆SiO2和SiO2/Al2O3改性,并用IR、XRD、TG-DSC对其表面结构进行了表征,用紫外-可见分光光度计对其紫外屏蔽性能进行了检测,采用Zeta电位测定仪、静态沉降实验等分析手段考察了改性前后纳米氧化锌在水体系中的分散稳定性。结果表明,在ZnO表面形成的包覆物是以非晶态形式存在的,通过表面包覆SiO2和SiO2/Al2O3改性后纳米氧化锌对紫外光的屏蔽性能有所下降,明显提高了氧化锌的表面羟基含量,有效改变了氧化锌的等电点,显著提高了纳米氧化锌在水中的分散稳定性。

Nano-ZnO coated with SiO2 and SIO2/Al2O3 was synthesized by chemical liquid deposition method. Both the coated and uncoated ZnO nanoparticles were characterized by IR, XRD and TG-DSC, their characteristics of UV-screen were detected by ultraviolet spectrometer. And the stability of specimens in water is analyzed through the instrument of Malveru Zetasizer Nano ZS90 and sedimentation velocity experimentation. Results show that the coated layer on ZnO surface is amorphous. After surface modification, UV-screen is decreased, and the adsorbed hydroxyl content of ZnO is increased. Moreover, the isoelectric point （IEP） of ZnO slurry is chanGed, and thestability of nano-ZnO in water is improved effectively.