Morphology Of ZnO Products Research Articles

Effect of Different C Aids on the Formation of ZnO by Microwave Solid Reaction

ZnO nanometer materials were synthesized by microwave reaction from ZnO micrometer powders with different C aids. Effect of C style on the morphology of ZnO products was studied. The result show that ZnO nanometer materials can not be formed by using directly high temperature evaporation from ZnO micrometer powders without C aids. Fine ZnO nanometer crystals can be obtained by using carbon black as aids. In this sample, most ZnO grains were nanometer particles with a size of about 100nm. And a small amount of ZnO grains were short rods with a length of 1~2μm and a average diameter of 100nm. Amounts of short columnar and long zigzag ZnO crystals can be obtained by using graphite as aids. One effect mechanism of ZnO crystalline was proposed. ZnO reacted C to form CO and CO2 gas. Concentration of CO/CO2 directly effects the morphology of ZnO in the products.

Facile solvothermal synthesis of abnormal growth of one-dimensional ZnO nanostructures by ring-opening reaction of polyvinylpyrrolidone

Abnormal growth of one-dimensional (1-D) ZnO nanostructures (NSs) have been accomplished with the assistance of polyvinylpyrrolidone (PVP) under a super high alkaline alcoholic solvothermal condition. The products were characterized by transmission electron microscopy (TEM), thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) and proton nuclear magnetic resonance (1H NMR) spectroscopy. The effect of synthetic conditions, such as reaction temperature and the addition of PVP, on the morphologies of ZnO products were investigated. The results show that PVP molecules had the significant role in the transformation of morphologies of ZnO NSs ranging from nanorods, nanoparticles to pyramids, as well as flower-like assembly features. The possible growth mechanism of ZnO pyramids was proposed based on ring-opening reaction of PVP.

Fabrication and Superhydrophobic Property of ZnO Micro/Nanocrystals via a Hydrothermal Route

Superhydrophobic ZnO micro/nanocrystals were fabricated on a large scale using a facile one‐pot hydrothermal process successfully. The morphologies and chemical composition of as‐synthesized ZnO were investigated by the scanning electron microscope (SEM) and X‐ray powder diffraction (XRD). The morphology of ZnO products changed from uniform size microrods to flower‐like micronanostructures, when the temperature changed from 120°C to 180°C. The morphology of ZnO was strongly affected by the pH. The wettability of the as‐synthesized ZnO micro/nanocrystals was studied by measuring water contact angle (CA). The largest static CA for water is 167°, which is closely related to both the ZnO micro/nanostructure and chemical modification. Furthermore, the as‐prepared ZnO surface showed superhydrophobicity for some corrosive liquids such as basic and acidic aqueous solutions. The CAs of the surface modified with ZnO prepared at 160°C were over 155° in the range of pH = 1–13.