Blue emission in mesoporous silica excited by synchrotron radiation

The optical properties of porous silica were studied by means of synchrotron radiation. We investigated the spectral properties of the blue photoluminescence band as a function of the porosity of the samples. In the whole set of samples the blue band is centered at about 2.8 eV, with main excitations at 5.0 and 6.0 eV. Time decay analysis indicates the contemporary presence of two contributions of photoluminescence.