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)ru dye onto high surface area hydrophilic fumed silica and d ispersing the ruthenium-loaded silica in a silicone rubber support. These s ensing films possess desirable properties including higher luminescence int ensity, larger response towards oxygen and more linear Stern-Volmer calibra tion curves than films prepared by simple mixing of the ruthenium dye with silicone rubber. However, the response time of these silica-containing film s in the recovery cycle is ca. 30-50% longer than the films without silica.