Photostable, Oxygen-Sensitive Optical Probe Based on a Homonuclear Terbium(III) Complex Covalently Bound to Functionalized Polydimethylsiloxane

A new oxygen-sensitive optical probe based on the [Tb(3,5-dcba)₃ ]⋅1/2 H₂ O (3,5-dcba=3,5-dichlorobenzoate) complex, which is chemically attached to a phosphine-oxide-functionalized polydimethylsiloxane is presented. The hybrid material shows green emission and transparency in the visible range. The optically sensitive probe is photostable under excitation at 350 nm and shows the highest oxygen sensitivity, I₀ /I₁₀₀ equal to 8.9 at 1 atm, among probes based on homonuclear lanthanide compounds. Furthermore its reversibility is demonstrated after several cycles ranging from 100 % N₂ to 100 % O₂ with response time of 8.5 s (N₂ →O₂ ) and recovery time of 49.5 s (O₂ →N₂ ).