Trifluoromethyl-substituted cyclometalated iridiumIII emitters with high photostability for continuous oxygen sensing

Trifluoromethyl-substituted cyclometalated Ir(III) complexes have been prepared and fully characterized. The photophysical and electrochemical properties of the complexes were investigated systematically. All iridium complexes exhibit high photoluminescence quantum yields, high oxidation potentials and good photostability against continuous irradiation. The optimum loading level of the Ir(III) complexes incorporated into oxygen-sensitive films has been discussed. Three different polymers were investigated for the development of efficient oxygen-sensitive films. All Ir(III) complexes immobilized in ethyl cellulose demonstrated quick responses to various oxygen concentrations and high sensitivity upon changes of oxygen partial pressure. These cyclometalated Ir(III) complexes with high photostability are potential candidates for online continuous monitoring of oxygen concentrations.