Effect of catalyst on the fluorescence quenching of [Tris (4, 7-diphenyl-1, 10-phenanthroline) ruthenium (II) dichloride] for dissolved oxygen detection

We present the effect of the catalyst for sol-solution preparation of tris (4,7-diphenyl-1,10-phenanthroline) ruthenium(II) dichloride on the fluorescence quenching behavior. Two types of [Ru(dpp)₃]²⁺ sol-solution were prepared with two types of catalyst namely acid hydrochloric (HCl) and ammonium hydroxide (NH₄OH) and each of them was mixed with the dye-solution to form [Ru(dpp)₃]²⁺ sol-gel solution. A polymer optical fiber tip was then coated by each of the solutions respectively by immersion method. A LED source at 460 nm was used as the excitation source and fluorescence emissions intensity was measured using a UV/VIS spectrometer. The results showed that the fiber optic coated with the solution using NH₄OH gave higher fluorescence intensity.