The mechanism for hydrothermal growth of zinc oxide

Facile Template-less Fabrication of ZnO Nanostructures;On the Consideration of Several Parameters

“…It is notable that due to absence of any surfactants, as templates, in the present work, the morphological evolution of ZnO products is obtained solely by hydrothermal reaction conditions and is dependent upon the concentration of the obtained Zn(OH) 2 4 . Although it was di cult to exactly nd out the growth mechanism of ZnO based on the present experiments and the previous reports [11,23,24,[26][27][28], we tried to explain how di erent morphologies with di erent sizes were formed.…”

“…In addition, Nicholas et al prove that the hydrothermal growth of ZnO occurs via the initial precipitation of "-Zn(OH) 2 , which is subsequently dehydrated and forms Wurtzite ZnO [27].…”

Prunus domestica dye extraction for fabrication of zinc oxide based dye-sensitized solar cells

“…The growth solutions were prepared by mixing equal molar concentrations of zinc nitrate and hexamethylenetetramine in distilled water at room temperature. The AZO coated substrates were dipped into the growth solution at the constant temperature of 905 o C for 2 hours for the ZnO nanostructures to grow [15]. After taking out from the solution these were rinsed with distilled water and dried in air at 4005 o C for 30 minutes.…”

Key role of terminal hydroxyl groups and visible light in the reactive adsorption/catalytic conversion of mustard gas surrogate on zinc (hydr)oxides

“…The latter was the initially formed stable crystalline compound in the precipitation reaction. Furthermore, by tracking the oxygen atoms via isotope labeling, they determined that the transformation occurs primarily via a solid state to a solid state path [2]. Yamabi and Imai [7] found that wülfingite Zn(OH) 2 was predominantly formed at pH 6.0-9.0, while würtzite ZnO was mainly obtained at pH 9.0-13.0 from the reaction of zinc sulfate heptahydrate (ZnSO 4 7H 2 O) with ammonium fluoride (NH 4 F), ammonium chloride (NH 4 Cl), ammonium nitrate (NH 4 NO 3 ), and ammonium sulfate ((NH 4 ) 2 SO 4 ) as complexing agents.…”

“…One of the quickest, economically feasible and green syntheses of zinc oxide/hydroxide is the addition of sodium hydroxide to a zinc salt solution. When NaOH is added to a Zn salt precursor solution, factors such as addition rate, final pH of a solution, and aging time have an effect on the crystal phase and structure [2][3][4]. Thus, the precipitation/formation of ZnO or Zn(OH) 2 can be promoted by controlling the addition rate of the NaOH precipitant.…”