Three-fold symmetrically distributed GaN nanowire (NW) arrays have been epitaxially grown on GaN/sapphire substrates. The GaN NW possesses a triangular cross section enclosed by (0001), (2112), and (2112) planes, and the angle between the GaN NW and the substrate surface is ∼62°. The GaN NW arrays produce negative output voltage pulses when scanned by a conductive atomic force microscope in contact mode. The average of piezoelectric output voltage was about -20 mV, while 5-10% of the NWs had piezoelectric output voltages exceeding -(0.15-0.35) V. The GaN NW arrays are highly stable and highly tolerate to moisture in the atmosphere. The GaN NW arrays demonstrate an outstanding potential to be utilized for piezoelectric energy generation with a performance probably better than that of ZnO NWs. © 2010 American Chemical Society.
Bibliographical noteKAUST Repository Item: Exported on 2020-10-01
Acknowledgements: This research was supported by DARPA (Army/AMCOM/REDSTONE AR, W31P4Q-08-1-0009), BES DOE (DE-FG02-07ER46394), KAUST, and NSF (DMS0706436, CMMI 0403671). Thanks are also due to the National Science Council of Taiwan, Republic of China, for a fellowship to study abroad (C.-T.H.) (N5C97-2917-1-007-110).
This publication acknowledges KAUST support, but has no KAUST affiliated authors.