Solid-state photoelectron transfer in powdery nanocomposites comprised of a sensitiser, photoacid generators and silica nanoparticles

Abstract

The dry beads milling of a mixture of 9,10-dipropoxyanthracene (DPA) as an electron donor and surface-modified silica nanoparticles was conducted in the absence or in the presence of a photoacid generator (PAG) as an electron acceptor to give powdery nanocomposites. Fluorescence measurements indicated no mechanochemical change in the crystal structure of DPA after the nanohybridisation. The co-milling with PAG resulted in solid-state fluorescence quenching, whereas quenching efficiency was considerably dependent on the nature of PAG. The solid-state sensitised photoacid generation through the electron transfer was demonstrated by the solid-state photocolouration of leuco-dye of crystal violet lactone.

Recent Advances in Monocomponent Visible Light Photoinitiating Systems Based on Sulfonium Salts

“…Second, the radical cations and the neutral radicals formed after photolysis should be stable enough to avoid radical recombination [178]. Considering that benchmark sulfonium salts naturally absorb in the UV range [179], visible light photopolymerization can be initiated only if photosensitizers are used [180,181]. However, efficacy of the photoinduced electron transfer relies on a bimolecular process that is strongly influenced by the viscosity of the resin.…”