Characterization and Correction of Temperature Effects on Ru(bpy)₃²⁺ Fluorescence Films Used in Dissolved Oxygen Sensor

Abstract

The spectral characteristic of the fluorescence film used in dissolved oxygen sensor is influenced by temperature. In this paper, we quantitatively studied the temperature effect of the dissolved oxygen sensitive film based on Ru (bpy)32+complexes. In order to study how it was affected, two experiments were designed. One experiment was carried out when the sensitive membrane was dipped into solution of saturated sodium sulfite, in which case, there was no oxygen interference. The other experiment was implemented when the sensitive film was exposed to air, while the influence of oxygen was constant. In the processes of both experiments, we adjusted the temperature around the sensitive membrane. When the temperature rising from 0°C to 45°C, the fluorescence intensity emitted from the sensitive film was reduced which in the first experiment decreased from 5030counts to 3845counts and in the second experiment from 2314counts to 1407counts. Then a method can correct the temperature effect was proposed. The curve of spectrum at 25°C was supposed to be the standard and spectrums at other temperatures was corrected to be consistent with it. The correction coefficient of every wavelength was got through our calculation. After multiplying the coefficients, fluorescence intensity at different temperatures was approximately equal and the differences caused by temperature were eliminated.