Silicon nanowires with permanent electrostatic charges for nanogenerators
Ronghui Que1, Mingwang Shao, Suidong Wang
1Institute of Functional Nano and Soft Materials (FUNSOM) & Jiangsu Key Laboratory for Carbon-based Functional Materials and Devices, Soochow University, Suzhou, Jiangsu 215123, People's Republic of China.
Nano Letters
|October 20, 2011
Summary
Silicon nanowires (SiNWs) exhibit robust, permanent electrostatic charges, overcoming electret instability issues. These stable SiNW electrets enable a durable nanogenerator for self-powered applications.
Area of Science:
- Materials Science
- Nanotechnology
- Solid-State Physics
Background:
- Electrets are dielectric materials with quasi-permanent electric charge or dipole polarization.
- Environmental factors like temperature and humidity often cause charge instability in electrets, limiting their practical applications.
Purpose of the Study:
- To investigate the potential of silicon nanowires (SiNWs) as stable electret materials.
- To explore the application of SiNW electrets in nanogenerators for self-powered devices.
Main Methods:
- Modified oxide-assisted growth was employed to synthesize silicon nanowires (SiNWs).
- The electret properties, including charge stability and surface potential, were characterized.
- A nanogenerator was fabricated using the SiNW electrets.
Main Results:
- SiNWs demonstrated permanent electrostatic charges and a surface potential up to 7.7 mV.
- The electret behavior of SiNWs proved exceptionally robust, maintaining stability even after 2 months of immersion in water.
- The fabricated nanogenerator produced an output power of 2.19 × 10(-11) W with a 2.2% conversion efficiency.
Conclusions:
- Silicon nanowires synthesized via modified oxide-assisted growth exhibit remarkable electret stability, overcoming limitations of conventional electrets.
- The robust electret properties of SiNWs enable the development of sustainable and stable nanogenerators for diverse self-powered applications.
- The permanent charges in SiNW electrets are attributed to the formation of alpha-quartz within the nanowires.
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