Structural evolution of self-assembling nanohybrid thin films from functionalized urea precursors

Hybrid organic-inorganic thin films exhibiting patterned structuring on the nanometer scale have been prepared through the controlled hydrolysis-condensation of enantiomerically pure chiral urea-based silyl compounds. The thin films are obtained by spin-coating of sols obtained via acid- or base-catalyzed hydrolytic condensation of these molecular precursors. A self-templating process is demonstrated via atomic force and transmission electron microscopy, showing the formation of nanometer size aggregates consisting of interconnected spherulates under acidic condition and of assembled fibers under basic conditions.