Fluorescence decay of the well-known fluorophore, ruthenium (II) 4,7-diphenyl-1,10-phenanthroline perchlorate, has been studied in a series of sol-gel matrices, including non-polar methyltrimethoxysilane (MTMS) and highly polar tetraethylorthosilicate (TEOS)-based gels. Systematic changes in composition and processing techniques have been fabricated to examine the structural properties of sol-gel silicates for possible oxygen sensor supports. Measurements were performed using both brush-coated and spin-coated sol- gel thin films as well as sol-gel monoliths. Gel compositions consisted of either 100% MTMS, 100% TEOS, or a 1:1 molar ratio of MTMS to TEOS. Quenching behavior was analyzed as a function of varying sol-gel composition, processing technique (spin-coated, brush-coated, etc.), and fluorophore concentration. The use of modeling techniques were employed to enable determination of possible singe or multi-exponential decay behavior in different sol-gel samples. Causes for the variations in quenching properties as a function of gel composition and processing technique were explained by a two-domain model. In addition, phase fluorimetric analysis was conducted on all doped sol-gel samples to determine the change in phase between the quenched and unquenched states of the films. Direct experimental phase data was compared to phase results calculated from the experimental lifetime data in order to examine the accuracy of the luminescence decay times. Possible design of sol-gel supports for oxygen sensors was also discussed.