Morphology‐photocatalytic properties‐growth mechanism for ZnO nanostructures via microwave‐assisted hydrothermal synthesis

Abstract

ZnO nanostructures with various morphologies including rod-like, sheet-like, needle-like and flower-like structures were successfully synthesized via a fast and facile microwave-assisted hydrothermal process. Reaction temperature, reaction time and the addition of NaOH were adjusted to obtain ZnO with different morphologies. Scanning electron microscopy(SEM), transmission electron microscope(TEM), X-ray diffraction (XRD) and ultraviolet spectrophotometer (UV) were used to observe the morphology, crystal structure, ultraviolet absorption and photocatalytic activity of the obtained ZnO. The results indicated that growth rate of ZnO nanostructure along [001] direction was more sensitive to temperature compared with those along [101] and [100] directions. The competition between anionic surfactant and OH − played an important role in the formation of ZnO with various morphologies. Flower-like ZnO had better ultraviolet absorption property and excellent photocatalytic activity than ZnO in the other morphologies. On the basis of the above results, a possible growth mechanism for the formation of ZnO nanostructures with different morphologies was described.

Correlation between structural and electronic order–disorder effects and optical properties in ZnO nanocrystals

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Photocatalytic Fuel Cell Using TiO₂/ZnO/Zn Photoanode for Greywater and Bacteria Abatements with Power Generation Concomitantly

“…4). E. coli is one kind of pathogenic microorganisms and its commonly present in the wastewater such as greywater can cause numerous enteric diseases [15,16]. Most importantly, this microorganism can threaten the ecological stability and public health even at low concentrations.…”

Synthesis and Characterization of Zinc Oxide Obtained by Combining Zinc Nitrate with Sodium Hydroxide in Polyol Medium

“…The solvothermal method with the use of polyols, multivalent alcohols with high boiling points, allows the reactions to occur at high temperatures with no need for high pressures or autoclaves, that's why it is a versatile and interesting method. It enables the control of the size and morphology of ZnO nanostructures [22][23][24][25][26] and it's also used for obtaining doped ZnO nanoparticles 27,28 . The polyols more often used are ethylene glycol, diethylene glycol, tetraethylene glycol and glycerol 29,30 , whose boiling points are 197.3, 245, 285 and 290 °C31 , respectively.…”