ABSTRACT
One-dimensional (1D) materials have stimulated much attention due to their promising potential in extensive applications [1]. The recent research in this field focuses on investigating the dependence of electrical transport and optical and mechanical properties on size and dimensionality [2,3]. Among them, semiconducting zinc oxide (ZnO), which has a wide bandgap of 3.37 eV and a large exciton binding energy of 60 meV, has attracted much attention due to its promising potential as a “future material” [4]. At ambient pressure and temperature, ZnO crystallizes in the wurtzite structures, as shown in Figure 52.1. This is a hexagonal lattice and is characterized by two interconnecting sublattices of Zn2+ and O2−, such that each Zn ion is surrounded by tetrahedral O ions and vice versa. This tetrahedral coordination gives rise to polar symmetry along the hexagonal axis. This polarity is responsible for a number of properties of ZnO, including its piezoelectricity and spontaneous polarization, and is also a key factor in crystal growth, etching, and defect generation. Many groups have focused on novel nanostructures with different shapes ranging from nanowires to nanobelts and even nanosprings. ZnO nanorods or nanowires are generally synthesized by four main techniques: chemical vapor deposition [5], metal–organic vapor deposition [6], aqueous solution method (equal to chemical bath deposition (CBD)) [7], and electrodeposition [8]. Wurtzite structure model of ZnO. https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9781315216089/1a39fa69-e426-4ca1-a1b7-b7d35c28e418/content/fig52_1.tif"/>
