Luminescence quenching of Ru(II) complexes in polydimethylsiloxane sensors for oxygen

• Published in: Journal of photochemistry and photobiology. A, Chemistry. Vol. 120; no. 1; pp. 15 - 21
• Main Authors: Bossi, Mariano L., Daraio, Marta E., F. Aramendı́a, Pedro
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 04-01-1999; Elsevier Science
• Subjects: Analytical chemistry; Chemistry; Exact sciences and technology; General, instrumentation; Luminescence; Oxygen; Polymer; Quenching; Ruthenium(II) diimines; Polymer; Oxygen; Ruthenium(II) diimines; Luminescence; Quenching; Performance evaluation; Dimethylsiloxane polymer; Fluorescence detector; Organic ligand; Transition metal Complexes; Chemical sensor; Luminescence decay; Matrix isolation; Luminescence quenching; Ruthenium Complexes; Platinoid Complexes; Gas detector
• ISSN: 1010-6030; 1873-2666
• DOI: 10.1016/S1010-6030(98)00418-3

The luminescence quenching of ruthenium(II)-tris(1,10-phenanthroline) and ruthenium(II)-tris(4,7-diphenyl-1,10-phenanthroline) by oxygen in films of commercial polydimethylsiloxane was studied by steady state and time-resolved methods. The decay kinetics is not monoexponential in the absence and in the presence of oxygen. It can be accurately described in all cases by the function exp(−
Bt
1/2), a particular case of the stretched exponential behaviour often found in solid media. The steady state and integrated time-resolved quenching efficiency coincide and show a downward curvature as a function of oxygen partial pressure. This dependence is explained by assuming a Freundlich type adsorption of oxygen in the dopants of the polymer. Both complexes render the same dependence of adsorbed oxygen on its partial pressure.