| Title | Highly Sensitive Carbon Nanotubes Coated Etched Fiber Bragg Grating Sensor for Humidity Sensing |
| Publication Type | Journal Article |
| Year of Publication | 2014 |
| Authors | Shivananju, BN, Yamdagni, S, Fazuldeen, R, Kumar, AKS, Nithin, SP, Varma, MM, Asokan, S |
| Journal | IEEE Sensors Journal |
| Volume | 14 |
| Pagination | 2615-2619 |
| Date Published | Aug |
| ISSN | 1530-437X |
| Keywords | Bragg gratings, Bragg wavelength shift, carbon nanotubes, carbon nanotubes coated etched fiber Bragg grating sensor, CNT coated EFBG, Etched fiber Bragg grating sensor, FBG-based humidity sensor, fiber core, Fiber gratings, fibre optic sensors, Humidity, humidity sensing, humidity sensors, linear response, nanosensors, Optical fiber sensors, refractive index, relative humidity sensing, Temperature sensors, water molecules |
| Abstract | The sensing of relative humidity (RH) at room temperature has potential applications in several areas ranging from biomedical to horticulture, paper, and textile industries. In this paper, a highly sensitive humidity sensor based on carbon nanotubes (CNTs) coated on the surface of an etched fiber Bragg grating (EFBG) sensor has been demonstrated, for detecting RH over a wide range of 20%-90% at room temperature. When water molecules interact with the CNT coated EFBG, the effective refractive index of the fiber core changes, resulting in a shift in the Bragg wavelength. It has been possible to achieve a high sensitivity of 31 RH, which is the highest compared with many of the existing FBG-based humidity sensors. The limit of detection in the CNT coated EFBG has been found to be 0.03 RH . The experimental data shows a linear response of Bragg wavelength shift with increase in humidity. This novel method of incorporating CNTs on to the FBG sensor for humidity sensing has not been reported before. |
| DOI | 10.1109/JSEN.2014.2312353 |
