Computational Modeling and Characterization of Nanoporous Films Assembled by Deposition of Au Nanoparticles

Nanoporous films assembled by low-kinetic-energy deposition of individual nanoparticles are complex nanomaterials for a variety of applications, from gas sensing to neuromorphic computing. We develop a numerical strategy for assembling metallic nanoparticles into 25-40 nm thick films from an arbitrary distribution of Au nanoparticles in terms of their initial size and shape. We characterize the structural properties of the assembled films as a function of the initial nanoparticle distribution. The morphology of the deposited nanoparticles affects nanofilm thickness, porosity, and its internal structure, including the length, type, and density of dislocations. Film porosity and the average dislocation length mainly correlate with the size of deposited nanoparticles. At the same time, thickness and dislocation density can also be affected by the shape of the larger nanoparticles deposited.