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Atomic Layer Deposition of Vanadium Dioxide and a Temperature-dependent Optical Model
Published on: May 23, 2018
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Reconfigurable Vanadium Dioxide Nanomembranes and Microtubes with Controllable Phase Transition Temperatures
Ziao Tian1, Borui Xu1, Bo Hsu2
1Department of Materials Science, State Key Laboratory of ASIC and Systems , Fudan University , 200433 Shanghai , PR China.
Nano Letters
|April 11, 2018
Summary
Researchers developed new vanadium dioxide (VO2) nanomembranes and microtubes. Rolling nanomembranes into microtubes controllably tunes VO2
Area of Science:
- Materials Science
- Nanotechnology
- Solid State Physics
Background:
- Vanadium dioxide (VO2) exhibits a phase transition with unique electrical and optical properties.
- Controlling the phase transition temperature of VO2 is crucial for practical applications.
- Existing methods for tuning VO2 properties are limited.
Purpose of the Study:
- To introduce novel free-standing vanadium dioxide (VO2) nanomembranes and microtubes.
- To demonstrate a method for controllably tuning the phase transition temperature of VO2.
- To explore the potential of these structures in device applications.
Main Methods:
- Fabrication of free-standing VO2 nanomembranes by thinning and etching.
- Rolling VO2 nanomembranes into microtubes with controllable diameters.
- Characterization of structural, mechanical, and thermal properties.
Main Results:
- Successfully fabricated VO2 nanomembranes and microtubes.
- Demonstrated that rolling-up VO2 nanomembranes into microtubes induces compressive strain, lowering the phase transition temperature.
- Showcased reversible transformation between microtube and nanomembrane structures.
- Developed a tubular microactuator device with low driving energy and large displacement.
Conclusions:
- The rolling-up process offers a novel and effective method for tuning VO2 phase transition temperature.
- VO2 nanomembrane-microtube structures exhibit tunable properties and reversible shape transformation, making them promising for device applications.
- The demonstrated microactuator highlights the practical potential of these novel VO2 structures.
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