O(2)-responsive chemical sensors based on hybrid xerogels that contain fluorinated precursors.

We report the development and analytical figures of merit associated with several new O(2)-responsive sensor materials. These new sensing materials are formed by sequestering the luminophore tris(4,7-diphenyl-1,10-phenanthroline)ruthenium(II) (Ru(dpp)(3)) within hybrid xerogels that are composed of two of the following methoxysilanes: tetramethoxysilane, n-propyl-trimethoxysilane, 3,3,3-trifluoropropyl-trimethoxysilane, phenethyl-trimethoxysilane, and pentafluorophenylpropyl-trimethoxysilane. Steady-state and time-resolved luminescence measurements are used to investigate these hybrid xerogel-based sensor materials and elucidate the underlying reasons for the observed performance. The results show that many of the Ru(dpp)(3)-doped composites form visually uniform, crack-free xerogel films that can be used to construct O(2) sensors that have linear calibration curves and excellent long-term stability. To the best of our knowledge, the Ru(dpp)(3)-doped fluorinated hybrid xerogels also exhibit the highest O(2) sensitivity of any reported Ru(dpp)(3)-based sensor platform.