Langmuir-Schaefer films of nafion with incorporated TiO2 nanoparticles

An easy method of incorporating TiO nanoparticles into Nafion perfluorinated ionomer is proposed. Ultrathin films of Nafion were prepared by employing the Langmuir-Schaefer (LS) technique. The pressure-area isotherm study of a Langmuir monolayer of Nafion at the air-water interface on different concentrations of NaCl as the subphase allowed us to find the best experimental conditions for the deposition of stable Langmuir-Schaefer films. Incorporation of TiO nanoparticles was performed by dipping Nafion LS films in a solution of TiO nanoparticles. The uniformity of the TiO incorporation was detected by UV-visible spectroscopy. The morphology of the Nafion, Nafion/TiO nanoparticles thin films, and the changes due to the annealing procedure were investigated by atomic force microscopy. Interestingly, the AFM investigation showed that Nafion and Nafion/TiO LS films have thermal stability up to 600°C.