One-Dimensional Zinc Oxide Nanomaterials for Application in High-Performance Advanced Optoelectronic Devices

Abstract

Unlike conventional bulk or film materials, one-dimensional (1D) semiconducting zinc oxide (ZnO) nanostructures exhibit excellent photoelectric properties including ultrahigh intrinsic photoelectric gain, multiple light confinement, and subwavelength size effects. Compared with polycrystalline thin films, nanowires usually have high phase purity, no grain boundaries, and long-distance order, making them attractive for carrier transport in advanced optoelectronic devices. The properties of one-dimensional nanowires—such as strong optical absorption, light emission, and photoconductive gain—could improve the performance of light-emitting diodes (LEDs), photodetectors, solar cells, nanogenerators, field-effect transistors, and sensors. For example, ZnO nanowires behave as carrier transport channels in photoelectric devices, decreasing the loss of the light-generated carrier. The performance of LEDs and photoelectric detectors based on nanowires can be improved compared with that of devices based on polycrystalline thin films. This article reviews the fabrication methods of 1D ZnO nanostructures—including chemical vapor deposition, hydrothermal reaction, and electrochemical deposition—and the influence of the growth parameters on the growth rate and morphology. Important applications of 1D ZnO nanostructures in optoelectronic devices are described. Several approaches to improve the performance of 1D ZnO-based devices, including surface passivation, localized surface plasmons, and the piezo-phototronic effect, are summarized.