An Optical Fiber ${\rm H}_{2}{\rm O}_{2}$-Sensing Probe Using a Titanium(IV) Oxyacetylacetonate Immobilized Nafion Coating on an Bent Optical Fiber Probe

An optical fiber sensor technique has been developed for monitoring trace H
₂
O
₂
in aqueous solutions. A titanium(IV) oxyacetylacetonate doped Nafion coating on the surface of a bent optical fiber probe was used as a transducer. Trace H
₂
O
₂
in an aqueous solution diffused into the polymer coating reacts with the sensing agent. The resulted product absorbs light with peak absorption wavelength at 360 nm, which is detected by using optical fiber evanescent wave absorption spectrometry. This sensor reversibly responses to trace H
₂
O
₂
in water, and has a detection limit (3σ) of 7.4
_*
10
^-8
mole H
₂
O
₂
/L. This fiber-optic sensor is immune of interferences from electromagnetic field which makes it useful in proton exchange membrane fuel cell researches.