ZnO Nanowire Growth

  • Zinc Oxide (ZnO) is a direct band-gap (E.g.=3.37eV) semiconductor with a large excitation binding energy (60meV), exhibiting near UV emission, transparent conductivity and piezoelectricity. Moreover, ZnO is biocompatible and can be used for biomedical applications without coating.

SEM image shows vertically aligned ZnO nanorods on GaN-coated sapphire - average length of 400nm.
Structures catalysed by Au nanoparticles. Courtesy of University of Cambridge Department of Engineering

ZnO Nanowire Growth for Electronics 

Electronics 

  • ZnO nanowires and nanorods are good candidates for nanometre scale electronic applications, such as sensors or field emission transistors, because of their high sensitivity to the chemical environment. The sensing process is related to oxygen vacancies on the surface that influence the electronic properties of ZnO.

ZnO Nanowire Growth for Optoelectronics 

Optoelectronics

  • ZnO nanowires and nanorods are also potentially good candidates for nanometre scale photonic device applications, ultraviolet photo-detectors and light emitting devices. Both p-type ZnO nanowires and n-type ZnO nanowires can be produced as positively and negatively charged semiconducting materials, this forms good foundation to make light emitting diodes (LED), in which, as an electron meets a hole, it falls into a lower energy level and releases energy in the form of a photon of light.

ZnO Nanowire Growth for Photovoltaics 

Photovoltaic

  • ZnO nanowires and nanorods can be  used for fabrication of solar cells that can be dye-sensitised using liquid or solid (hole conductor) electrolyte, because ZnO has a wide bandgap, high charge carrier mobility and can give a high surface area for efficient dye-sensitization and light harvesting.

ZnO Nanowire Growth for Chemistry 

Chemistry

  • ZnO nanowires and nanorods can promote catalyst reactions with light as energy source, i.e. they can be used as photocatalysts.

ZnO Nanowire Growth for Biomedical 

Biomedical

  • The biocompatibility of ZnO nanowires and nanorods along with their electro-optical properties makes them suitable for active biomedical devices.