In situ photopolymerization of pyrrole in mesoporous TiO2.

We examined mesoporous TiO(2) as a photosensitizer and template for creating hybrid TiO(2)-polypyrrole materials. Optical excitation of mesoporous TiO(2) was used to generate the electronic potential necessary for the oxidation and polymerization of the pyrrole monomer. The photopolymerization process was monitored by the quartz crystal microbalance, nitrogen sorption, and thermogravimetric techniques. In situ generation of polypyrrole was observed to be self-limiting after approximately 20-30% filling of the mesoporous TiO(2) network. In situ generation of a complementary phase by means of charge transfer from an active host phase represents an alternative means of assembling hybrid inorganic-organic materials with potential applications ranging from electrocatalysis to photovoltaics.