NIRT: Manufacturing of Novel Continuous Nanocrystalline Ceramic Nanofibers with Superior Mechanical Properties

University Of Nebraska-Lincoln, Lincoln NE

Investigators

Abstract

This proposal was received in response to Nanoscale Science and Engineering initiative, NSF 01-157, category NIRT. Nanostructured materials (NSMs) with unusual and extreme properties will play a key role in many emerging technologies. However, manufacturing of NSMs with the desired properties is highly complex and currently is over-reliant on empirical data. In this proposal, a novel manufacturing process producing a new class of ceramic materials, i.e. continuous ceramic nanofibers, will be addressed. The novel sol-gel electrospinning technique (U.S. patent pending), invented recently by two of the PI's (Dzenis and Larsen), produces ceramic fibers of submicron diameters with potentially extreme thermomechanical properties. This technique will be analyzed and optimized for the production of nanocrystalline ceramic nanofibers with superior mechanical properties, based on a comprehensive, multidisciplinary research effort. The research team will develop an efficient and robust computational methodology for simulating realistic nanocrystalline nanofibers and their mechanical response at finite temperatures. A novel atomistic-continuum modeling approach based on a hybrid Monte-Carlo finite element technique will be developed and used. The models will be applied to design strong nanofibers by predicting the effects of the chemical composition and atomic structures of grain boundaries and defects on mechanical properties. The results will be used to develop chemistry and to direct manufacturing of strong nanocrystalline nanofibers. The achievement of the enhanced mechanical properties of the resulting nanofibers will be demonstrated experimentally utilizing novel mechanical characterization techniques based on scanning probe microscopy. As a result of this research, the new nanomanufacturing method will be further developed based on the atomistic-continuum modeling. New nanocrystalline ceramic nanofibers with superior mechanical properties will be produced. The combined manufacturing and model-based optimization will allow the mechanical properties of the nanofibers to be tailored to specific needs of the end user. This general, modeling-driven approach will be applicable to other nanomanufacturing processes and nanomaterials. This technology will be a significant part of future nanotechnology efforts. This research program will impact other key areas of nanotechnology where radical improvement of mechanical properties is critical, e.g., nanostructured membranes for ultrafiltration and other separation processes, nanoreinforcing elements for nanocomposites, supports for nanostructured catalysts, and many others. A multidisciplinary education plan will include development of interdisciplinary graduate courses on materials synthesis technology, computational materials science, and nanoscale materials characterization. Graduate and undergraduate research assistants will work within the various research groups on computational and experimental aspects of the research. Planned interactions with researchers at national laboratories will provide graduate and undergraduate students with additional educational exposure.