Synthesis and Spectroscopy of TPP Derivative-Doped Silica Gels by Sol-Gel Process

Abstract

We have reported the incorporation of the photochemical hole-burning (PHB) dyes to the silica gels and the observation of spectral holes [1-3]. The porphyrins are well-known PHB dyes. However, in acidic solutions, many porphyrins change their forms into dication which is inactive in PHB [4]. So we have developed two-step sol-gel processes from the hydrolysis of TMOS with NaOH, and successfully incorporated free-base TPPS, a kind of porphyrin, in the silica gels [5].