A review of growth and characterization of ZnO nanostructures for optoelectronic sensor and energy harvesting applications

In recent years a substantial amount of research has focused on the mechanical and electro-optical properties of ZnO nanowires (NWs). Initially, a significant portion of the work involved developing either single NWs or NW arrays for photo detection at ultraviolet (UV) wavelengths, and the innovation and performance of such devices have subsequently and progressively advanced. In addition, several new areas of ZnO NW research have since appeared, with energy harvesting at the forefront. The piezoelectric potential of nanowires has been a source of considerable interest, and novel concepts have been reported, including devices that convert thermal energy and sound waves into electrical power. In this paper we will address recent work (mostly published within the past couple years) on both ZnO NW based UV photodetectors and energy harvesting, seeking in the process to identify notable and innovative features that are advancing ZnO NW technology and nanodevice performance.