Fabrication of ZnO Nanorods in One Pot via Solvothermal Method

Abstract

AbstractIn this article, we reported a low temperature solvothermal method to synthesize ZnO nanorods in one pot. In order to study the growth mechanism of ZnO nanorods, various preparative parameters, such as zinc species concentration, the molar concentration ratio of hydroxide [OH‐] to zinc species [Zn2+], and surfactants, have been systematically examined. According to the analysis, the aspect ratio of ZnO nanorods was enlarged with the increase of the concentration ratio of [OH‐] to [Zn2+]. However, the mean diameter only causes subtle change. Additionally, the influence of surfactants was studied by two different kinds of surfactant, ethylenediamine (EDA) and hexadecylamine (HDA). From transmission electron microscopy analysis, the aspect ratio of ZnO nanorods was similar to that without adding surfactant. However, the green emission caused by oxygen defects or others can be omitted while the surfactants were added into the reaction. Herein, the growth mechanism was proposed to relate to the element of coordination polyhedron presented in the interface. When terminal vertex bonds with more growth units, the interface has higher growth rate for the crystal formation. Besides, the reaction medium also affects the growth mechanism of ZnO nanorods. In an alkali medium, the larger hindrance effect of ONa‐ ions at the interface of (0001) and ( 01 1¯ 1¯ ) faces, the growth rates of (0001) and ( 01 1¯ 1¯ ) faces have a great hindrance relative to other crystal faces.