The performance of oxygen sensing films with ruthenium-adsorbed fumed silica dispersed in silicone rubber

Oxygen sensing films were prepared by adsorbing the tris(4,7-diphenyl-1,10-phenanthroline)ruthenium dye onto high surface area hydrophilic fumed silica and dispersing the ruthenium-loaded silica in a silicone rubber support. These sensing films possess desirable properties including higher luminescence intensity, larger response towards oxygen and more linear Stern–Volmer calibration curves than films prepared by simple mixing of the ruthenium dye with silicone rubber. However, the response time of these silica-containing films in the recovery cycle is ca. 30–50% longer than the films without silica.