Vertically Aligned ZnO Nanorods

The science behind the research

Research on zinc oxide nanowires (ZnO NWs) has been one of the hottest topics in recent years due to their unique properties and potential applications particularly in electronic and opto- electronics fields. The lack of central symmetry in ZnO wurtzite structure results in strong piezoelectric and pyroelectric proper- ties, which enables ZnO nanowires to be used as mechanical actuators and piezoelectric sensors.

Furthermore, a combination of the wide-bandgap (3.37 eV) of ZnO NW, large exciton binding energy (60meV) at room temperature, as well as enhancement of radiative recombination due to carrier confinement allows ZnO NWs based optoelectronic devices to be functional at a lower threshold voltage and emit UV light at room temperature. Thus, ZnO NWs have potential applications in nanoscale field emitter in flat panel displays [3], room tempera- ture UV lasers, and solar cells. Moreover, the naturally high surface-to-volume ratio of quasi one-dimensional nanowires has made them contenders for chemical sensor such as oxygen sensor.

Ongoing research

 Fig 1. Schematic diagram of the c axis of crystal grains in ZnO thin films deposited at (a) 155◦C, (b) 175◦C and (c) 280◦C

Schematic diagram of the c axis of crystal grains in ZnO thin films.jpg
Fig 2. Homeoepitaxial growth of ZnO nanowires by the CVD method on ZnO thin films deposited at (a) 155◦C; (b) 175◦C and (c) 280◦C. The synthesis time of ZnO NWs was 30 min for each type of ZnO film

Homeoepitaxial growth of ZnO nanowires on ZnO thin films.jpg

 Recent publications


 For further information contact Prof Kwang-Leong Choy
+44 (0)20 7679 3855 | k.choy@ucl.ac.uk