Synthesis of ZnO Nanostructures by Hydrothermal Method

Abstract

Abstract. ZnO was synthesized by the hydrothermal method using proper aqueous solutions of ZnCl 2 and NaOH, as the main raw materials, corresponding to the molar ratio of Zn , amount of PEG) influence the morphology and the dimensions of the product. Increasing the residence time from 1 h → 3 h → 20 h, the amorphous regions illustrated in SEM images are decreased and the number and dimensions of the obtained single or branched rods of the final product are increased. Avoiding the use of additional water, i.e. the denominator in the aforementioned ratio, mL, water, is equal to zero, but simultaneously using ethanol, the ZnO material is mainly amorphous. Increasing the amount of the additional water without ethanol, no amorphous material is observed and single rods or flowerlike/starlike structures having ends of regular hexagonal pyramid structure, are formed. Increasing the proportion of PEG, many flowerlike or starlike branched structures having ends of regular hexagonal prismatic structure, are formed. The ZnO materials having much of amorphous regions do not show XRD peaks. On the other hand, the crystalline ZnO materials show many XRD peaks, which are indexed and they correspond to the wurtzite-structured (hexagonal) ZnO. Furthermore, the lattice constants  and c are determined.

Cell responses to two kinds of nanohydroxyapatite with different sizes and crystallinities

“…[20][21][22] In this study, rod-like nanohydroxyapatite with an average diameter of 23 ± 5 nm or 16 ± 3 nm were obtained using simple heating in water. Homogeneous nanohydroxyapatite with different sizes and crystallinities were used to investigate the effects of nanohydroxyapatite on cell responses.…”

Improving the electrochemical properties of polyamide 6/polyaniline electrospun nanofibers by surface modification with ZnO nanoparticles

“…29,30 Aer the nucleation process, the increased particle solubility could result in growth of an individual nanostructure aggregation and/or coarsening. 25,31,32 PEG 8000 and PEG 4000 were not very efficient as surfactants, yielding shapeless and large grain originated from random aggregation process between small particles. Thus, our results indicate that the use of PEG surfactant with longer hydrophobic chains leads to nanoparticles with larger sizes.…”

A comparative study of photocatalytic degradation of Xylenol Orange dye under natural sunlight over ZnO nanoparticles synthesized via mechanochemical and hydrothermal assistance routes

“…Eco-friendly and biocompatible nature and good thermal stability make ZnO most hopeful contestant for electronic and optoelectronic applications [11]. Nanosized ZnO materials can be gained by using various synthetic routes for instance mechanochemical [12], chemical precipitation [13], solution combustion [14], sol-gel method [15], hydrothermal synthesis [1,10,16], etc. Within these methods of ZnO synthesis mechanochemical and hydrothermal methods are quite suitable to control the particle size.…”