Thermal Stability of CdSe/ZnS Quantum Dot-Based Optical Fiber Temperature Sensor

Abstract

Recently, Quantum Dots (QDs) have been widely studied due to their peculiar optical properties, and applied to various fields such as biomarker, LED device, Fluorescence Resonance Energy Transfer (FRET) sensor, and temperature sensor. In this study, we have prepared optical fiber temperature sensor using CdSe/ZnS QDs as sensing media. Carboxylated CdSe/ZnS QDs have been immobilized on the surface of optical fiber by EDC/ NHS crosslinking reaction. The PL spectra of QDs immobilized on optical fiber are dependent on the size of QDs and ambient temperature. Linear relation has been observed between PL intensity and temperature, and emission peak wavelength and temperature at the range of 25 and 135°C. The PL intensity of QDs has been greatly attenuated after repeated thermal cycle, resulting in poor thermal stability. But the temperature sensor with red QDs show constant slope of PL intensity vs. temperature after 5th cycle.

Keywords:

• CdSe/ZnS Quantum Dots
• optical fiber sensor
• temperature sensor

Acknowledgment

This work was supported by the National Research Foundation (NRF) grant funded by the Korea government (2010-0029277).