Silicon Carbide Nanocone and Heterostructure Formations Catalyzed by the Release of Carbon-Encapsulated Metal Nanoparticles

University Of Pittsburgh, Pittsburgh PA

Investigators

Abstract

Technical: This project is to study growth mechanism of nanostructures that are grown using encapsulation and controlled release of metal catalyst. The controlled catalyst release allows the exposed size/area of the catalyst be tailored, which leads to growth of unusual nanostructures, such as nanocones made of silicon carbide. The goal of the research project is to gain new mechanistic knowledge of all stages of the metal-catalyzed nano- and hetero-structure formation including the migration of the metal nanoparticle from the carbon shell and agglomeration behavior, the formation of the SiC at the metal/nanocone interface, and the nucleation and initial growth of the heterostructures. The primary research tool is transmission electron microscopy (TEM) and both in-situ and ex-situ TEM experiments will be carried out. Electrical and property measurements will be used to establish the synthesis-structure-property relationships. The potential outcome of the project will be a predictive tool for the manufacturing of specific nanowires with a precise distribution and geometry, as well as branched structures, and how processing conditions, such as temperature, size, and type of catalyst material, will alter the nanowire morphology, structure, and properties. Non-technical: The project addresses fundamental research issues in a topical area of importance to materials science. It aims for a quantitative and mechanistic understanding of the catalytic reaction governing one-dimensional nanostructure formations. Such knowledge is necessary for the design-based production of nanodevices with specific architectures and properties. The project constitutes an effective integration of research and education through training of postdoctoral, graduate, and undergraduate students in nanoscience and nanotechnology. The in-situ TEM nanocharacterization represents a unique opportunity for the students. The research program will also contribute to a new suite of graduate-level courses in nanotechnology, particularly nanofabrication and nanocharacterization. Undergraduate education will be enhanced via undergraduate summer research and senior projects.