Piezoelectric Nanogenerators Based on Zinc Oxide Nanowire Arrays

American Association for the Advancement of Science (AAAS) - Tập 312 Số 5771 - Trang 242-246 - 2006
Zhong Lin Wang1,2,3, Jinhui Song1,2,3
1Department of Advanced Materials and Nanotechnology, College of Engineering, Peking University, Beijing 100871, China
2National Center for NanoScience and Technology, Beijing 100080, China
3School of Materials Science and Engineering Georgia Institute of Technology Atlanta GA 30332 USA

Tóm tắt

We have converted nanoscale mechanical energy into electrical energy by means of piezoelectric zinc oxide nanowire (NW) arrays. The aligned NWs are deflected with a conductive atomic force microscope tip in contact mode. The coupling of piezoelectric and semiconducting properties in zinc oxide creates a strain field and charge separation across the NW as a result of its bending. The rectifying characteristic of the Schottky barrier formed between the metal tip and the NW leads to electrical current generation. The efficiency of the NW-based piezoelectric power generator is estimated to be 17 to 30%. This approach has the potential of converting mechanical, vibrational, and/or hydraulic energy into electricity for powering nanodevices.

Từ khóa


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U.S. patent pending.

Supported by NSF grant DMR 9733160 the NASA Vehicle Systems Program and Department of Defense Research and Engineering and the Defense Advanced Research Projects Agency. We thank X. Wang W. L. Hughes J. Zhou and J. Liu for their help.