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Updated: Jan 28, 2026
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Precision Milling of Carbon Nanotube Forests Using Low Pressure Scanning Electron Microscopy
Published on: February 5, 2017
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Carbon Nanotube Based γ Ray Detector
Sun Jin Kim, Honglu Wu1, Dong-Il Moon
1NASA Johnson Space Center , Houston , Texas 77058 , United States.
ACS Sensors
|March 9, 2019
Summary
A novel single-walled carbon nanotube (SWCNT) γ ray detector bypasses traditional scintillation. It uses changes in SWCNT conductance, driven by radiation-induced oxygen adsorption, for sensitive detection and dose rate differentiation.
Area of Science:
- Materials Science
- Radiation Detection
- Nanotechnology
Background:
- Conventional gamma ray detectors often rely on scintillation mechanisms.
- Single-walled carbon nanotubes (SWCNTs) possess unique electrical properties sensitive to surface interactions.
Purpose of the Study:
- To demonstrate a gamma ray detector based on single-walled carbon nanotubes (SWCNTs).
- To investigate the sensing mechanism involving radiation-induced oxygen adsorption on SWCNTs.
- To evaluate the detector's response to total dose and dose rate.
Main Methods:
- Fabrication of a two-terminal SWCNT resistor.
- Exposure of the SWCNT resistor to gamma ray radiation.
- Monitoring changes in the electrical conductance of the SWCNT in response to radiation.
- Analysis of radiation-induced oxygen dissociation and adsorption on the SWCNT surface.
Main Results:
- The SWCNT-based device functioned as a gamma ray detector without a scintillation mechanism.
- Gamma ray exposure altered the electrical conductance of the SWCNT.
- The detector demonstrated sensitivity to gamma ray total dose.
- The detector successfully distinguished radiation dose rates from 2.4 to 16.4 R/min.
Conclusions:
- A novel SWCNT-based gamma ray detector has been successfully demonstrated.
- The sensing mechanism relies on the modulation of SWCNT electrical properties by radiation-induced surface oxygen species.
- The detector exhibits potential for sensitive gamma ray detection and dose rate assessment.
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