Modeling Mesoporous Nanoparticulated TiO2 Films through Nanopolyhedra Random Packing

We present an innovative methodology for the computer simulation of mesoporous nanoparticulated oxide films based on the random packing of faceted nanopolyhedra in the form of bifrustums, reproducing the experimentally observed TiO2 anatase bifrustum shape. A computer simulation employing nanospheres as packing objects was preliminary considered to verify the validity of the developed procedure. The pore size distribution and other fundamental characteristics of the simulated films (porosity, radial distribution function, coordination number, contact number) are computed for nanospheres and nanopolyhedra simulated films. Our results show that the use of faceted bifrustums, while involving a computationally more demanding procedure, is essential to attain a reliable description of the morphology and local three-dimensional structure of mesoporous TiO2 nanoparticles films.