In‐situ Synthesis and Photoluminescence of a Europium Porphyrin Complex Incorporated in the Silica Matrix

A practicable synthesis method is explored to synthesize a europium porphyrin complex in which a water‐soluble positively charged 5,10,15,20‐tetrakis(4‐trimethylammoniophenyl)porphyrin iodide, H2TMePPI, is immobilized into the sol‐gel silica matrix and then in‐situ metallized with the Eu3+ ion. The product is characterized by means of the solid UV diffusion reflection spectra, fluorescence spectra, and thermal gravimetric analysis (TG). The solid UV diffusion reflection spectra show that the number of Q bands in the product is less than that of the H2TMePPI ligand, which is one of the important characteristics of porphyrin metallization. The fluorescence spectra of the product are different from that of the silica doped with free Eu3+ ions, implying the different function of Eu3+ ions in the product. The TG curves show that the thermal stability of the Eu(III)TMePPI entrapped into silica is higher than that of the H2TMePPI. The effect of a heat treatment and an UV‐light irradiation on the photoluminescence properties of the composite is investigated in details. The stronger interaction between Eu(III)TMePPI and SiO2 in the composite is responsible for the different spectra.