This project proposes to develop multiscale mathematical models and algorithms for simulating the growth of a coating on a nanofiber. There is potential application for coated nanofibers, and the nanotubes that result after dissolution of the nanofiber cores, in the areas of filtration, composites, biomedicine, and electronics. The ever increasing demand for these high quality nanomaterials applications drives the need for models that describe the coating process as well as models that describe the material and electromagnetic properties of manufactured nanofibers and nanotubes. The coating of nanofibers by physical vapor deposition (PVD) methods is a process that is only partially understood. While data on nanodeposition techniques have been collected for over a decade, a comprehensive quantitative model of the coating process has not yet been developed. The proposed research addresses this timely need by outlining a plan to develop truly multiscale models and simulations of coating growth at the continuum length scale while proceeding hand-in-hand with experimental validation. The PVD method allows for control over the experimental conditions so that comparisons between the experimental results and the model predictions will be straightforward. The plan to link asymptotic analysis, numerical simulation, quantum mechanics and molecular dynamics constitutes a major step in the study of nanoscale phenomena. The models and simulations will connect global continuum models in a PVD plasma reactor, local nanoscale models around a coated fiber, and quantummechanical and molecular dynamics models at the atomistic scale. These models will provide inputs to a macroscopic scale model of the coating growth so that the morphology of the coating can be tracked via a level set method. The overall goals of the multiscale modeling, simulation, and experimental efforts are to provide an understanding of how PVD process parameters affect the coating growth, to identify an optimal range of parameters for controlling the growth, to explain experimental observations of coating growth that are not well understood, and to determine the effective electromagnetic properties of the completed product.
This project proposes to develop multiscale mathematical models and algorithms for simulating the growth of a coating on a nanofiber. The coating of nanofibers with specific materials is a relatively new process for producing coated nanofibers and nanotubes (that result after removing the nanofiber cores). These nanostructures have many potential applications in filtration, composites, biomedicine, and electronics. The proposed combination of modeling and experimental efforts will help to address the fundamental unanswered questions concerning the physics and chemistry of nanofiber coating and the properties of the coating. In particular, this project will provide the understanding necessary to control the coating thickness and uniformity to produce nanotubes with desired dimensional features. In addition to its impact on scientific research, this project will enhance the training of graduate students in nanoscale modeling. This is essential for the development of a strong industrial base in nanotechnology. This research project will allow The University of Akron to develop the expertise necessary to augment existing programs to include a specialization in nanotechnology modeling, at the graduate and the undergraduate level. Further, it is anticipated that the enhanced understanding of nanoscale manufacturing processes gained during this research effort will allow manufacturers to improve existing products and to develop new products.
