| Article ID | Journal | Published Year | Pages | File Type |
|---|---|---|---|---|
| 463434 | Optical Fiber Technology | 2013 | 5 Pages |
A novel fiber optical fiber hydrogen sensor based on etched fiber Bragg grating coated with Pd/Ag composite film is proposed in this paper. Pd/Ag composite films were deposited on the side-face of etched fiber Bragg grating (FBG) as sensing elements by magnetron sputtering process. The atomic ratio of the two metals in Pd/Ag composite film is controlled at Pd:Ag = 76:24. Compared to standard FBG coated with same hydrogen sensitive film, etched FBG can significantly increase the sensor’s sensitivity. When hydrogen concentrations are 4% in volume percentage, the wavelength shifts of FBG-125 μm, FBG-38 μm and FBG-20.6 μm are 8, 23 and 40 pm respectively. The experimental results show the sensor’s hydrogen response is reversible, and the hydrogen sensor has great potential in hydrogen’s measurement.
► Etched FBG combined Pd/Ag composite films as sensing elements was first proposed. ► SEM results show that Pd/Ag composite film has good mechanical performance. ► Etched FBG can significantly increase the sensor’s sensitivity. ► FBG hydrogen sensors show linearity response for 1.5–4% hydrogen concentrations. ► The experimental results show the sensor’s hydrogen response is reversible.
