Submicrometer organic silica gel fiber for oxygen sensing

We introduce the electrospinning method into fabricating oxygen-sensitive submicrometer scale optical fiber. Uniform tris (4,7-diphenyl-1,10-phenathroline) ruthenium(II) dichloride ([Ru(dpp)(3)](2+)Cl(2))-doped fibers with a diameter of 900 nm are obtained by electrospinning the organic silicon sol solution derived from tetraethyl orthosilicate and n-Octyltriethoxysilane (C(14)H(32)O(3)Si). The experimental results show that the single gel fiber exhibits excellent optical and sensing properties. A laser with a wavelength of 452 nm can be efficiently launched into the fiber and guide along the fiber to excite the fluorescence. Then, we find that [Ru(dpp)(3)](2+)-gel fiber has favorable optical and sensing characteristics, and the Stern-Volmer plots are linear in the full concentration range of O(2) (0-100 vol. %). The ratio of I(0)/I(100), where I(0) and I(100) respectively represent the fluorescence intensities of the fiber exposed to 100% N(2) and 100% O(2), as the sensitivity of the fiber is 3.5. Simultaneously, the fiber can make a quick response within 100 ms. This method provides an effective and convenient way to fabricate highly uniform nanoscale or microscale optical waveguides for photonic devices.