Surface modification of nanostructured hexagonal ZnO powder using amorphous silica powder via low temperature sol-gel process

摘要

Background: Nanostructured ZnO powders have been given lot of research interestscompared to its bulk counterpart because of its good physical and chemical propertiesfor variety of applications. However, the photocatalytic activity and poor compatibilityto other organic compounds hinders the other potential industrial applications of ZnOpowder. Surface modification process is one way of overcoming this limitation of ZnOpowders using surface capper with good physical and chemical compatibility with ZnO.Objective: This work is focused on the investigation of the surface modification effectsof amorphous and crystalline silica powders to the as-synthesized ZnO hexagons.Results: The surface of hexagonal ZnO powders was modified by incorporating variousmasses of amorphous silica at room temperature. Tips of ZnO rods turned tohemispherical from hexagonal after silica incorporation. EDX detected the presence ofelements Si, O, and Zn on the surface of ZnO. Infrared spectroscopy further supportthat SiO2 was adhered to ZnO due to the Si-O-Zn band observed in the IR spectra. Xraydiffraction results verified the presence of amorphous SiO2 and the polycrystallinenature of the samples having particle size in nanometer scale. Conclusion: Surfacemodification of hexagonal ZnO was successfully achieved using amorphous silicapowder specifically using 0.1 grams of amorphous silica. Increasing the mass ofamorphous silica resulted into flaky structural features. Crystalline silica powderhowever disrupts the growth of ZnO nanostructures.