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Room temperature electrical and thermal switching CNT/hexadecane composites.
1Key Laboratory of Radiation Beam Technology and Materials Modification of Ministry of Education, College of Nuclear Science and Technology, Beijing Normal University, Beijing 100875, P. R. China.
Advanced Materials (Deerfield Beach, Fla.)
|July 17, 2013
Summary
Surface-functionalized carbon nanotube (CNT)/hexadecane composites exhibit a large conductivity contrast during a phase transition. This enhancement in electrical and thermal conductivity makes them suitable for advanced material applications.
Area of Science:
- Materials Science
- Nanotechnology
- Physical Chemistry
Background:
- Carbon nanotubes (CNTs) are known for their unique electrical and thermal properties.
- Phase-change materials offer potential for tunable conductivity.
- Combining CNTs with phase-change materials can lead to novel composite properties.
Purpose of the Study:
- To investigate the electrical and thermal conductivity of surface-functionalized CNT/hexadecane composites.
- To explore the impact of CNT surface modification on composite properties.
- To demonstrate the large conductivity contrast achievable via a first-order phase transition.
Main Methods:
- Synthesis of surface-functionalized CNTs.
- Fabrication of CNT/hexadecane composites.
- Measurement of electrical and thermal conductivity across the phase transition temperature.
- Analysis of the effect of surface modification on conductivity and stability.
Main Results:
- A large contrast in electrical conductivity (over 10^5 times) was observed.
- Thermal conductivity varied up to 3 times at 18 °C.
- Surface modification of CNTs enhanced conductivity contrast and composite stability.
Conclusions:
- Surface-functionalized CNT/hexadecane composites show significant potential for applications requiring large, switchable conductivity.
- The observed phase transition behavior offers a pathway for developing advanced functional materials.
- Optimized CNT surface modification is crucial for maximizing performance and stability.
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