Hybrid fiber gratings coated with a catalytic sensitive layer for hydrogen sensing in air.
Using hydrogen as fuel presents a potential risk of explosion and requires low cost and efficient leak sensors. We present here a hybrid sensor configuration consisting of a long period fiber grating (LPFG) and a superimposed uniform fiber Bragg grating (FBG). Both gratings are covered with a sensitive layer made of WO(3) doped with Pt on which H(2) undergoes an exothermic reaction. The released heat increases the temperature around the gratings. In this configuration, the LPFG favors the exothermic reaction thanks to a light coupling to the sensitive layer while the FBG reflects the temperature change linked to the hydrogen concentration. Our sensor is very fast and suitable to detect low hydrogen concentrations in air whatever the relative humidity level and for temperatures down to -50 degrees C, which is without equivalent for other hydrogen optical sensors reported so far.
Electromagnetism and Telecom Unit, Faculté Polytechnique de Mons, 31 Boulevard Dolez, Mons 7000, Belgium. christophe.caucheteur@fpms.ac.be
Christophe
C
Caucheteur
Marc
M
Debliquy
Driss
D
Lahem
Patrice
P
Megret
D000388:Air / Q000032:analysis*; D002384:Catalysis; D004784:Environmental Monitoring / Q000295:instrumentation*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006859:Hydrogen / Q000032:analysis*; D055100:Optical Fibers; D012031:Refractometry / Q000295:instrumentation*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014159:Transducers
D006859:Hydrogen