Nanocomposite fabrication via direct ultra-fast laser ablation of titanium in aqueous monomer solution

A novel approach to fabricating nanocomposites comprising inorganic nanoparticles embedded in an organic matrix is presented. Ultra-fast laser ablation of a titanium metal target in aqueous ε-caprolactam monomer solution is used to produce ultra-small TiO₂ nanoparticles and to simultaneously initiate the polymerization of the monomer without the use of chemicals. The spectroscopic analysis and TEM studies reveal the formation of an organic matrix and its conjugation to the nanoparticles' surface. The laser beam induces the formation of TiO₂ nanoparticles, which subsequently act as photoinitiators of the polymerization of ε-caprolactam upon absorbing the photon energy provided by the unfocused part of the beam. This work can open new pathways for cost-effective and environmentally friendly nanocomposite production, in one step. (letter)