Intellectual Merit: The long-term objective of this career plan is to develop and demonstrate a generalized enabling framework of principles for the design and reaction engineering of ultra-small metal oxide objects of complex morphology and structure. Specifically, the PI proposes to understand and manipulate the novel mechanisms and thermodynamics that govern the liquid-phase engineering of a unique class of single-walled mixed oxide nanotubes (with exceptionally small lengths of 20-100 nm and diameters 2-4 nm) and single-walled nanoshells (with diameter < 5 nm), all with complex and ordered internal structures. The ability to engineer the shape, size, structure, and composition of nanoscopic metal oxide objects at very small length scales - using only the minimum quantity of matter necessary - is highly attractive (but thus far elusive). A number of emerging applications could exploit the range of novel and drastically tunable electronic, optical, catalytic, transport, and mechanical properties arising from the unique shape, size, and structural complexity of these objects. Such a development would underscore the full potential of advanced chemical processing approaches for nanoscale science and technology, and can overcome limits imposed by current materials and processes. The PI's recent work has led to a proposed long-term molecular engineering strategy (summarized as 'amorphous nanoparticle condensation and rearrangement') that offers intrinsic advantages over current templating or catalytic approaches, and produces ultra-small metal oxide objects with complex structures. During the five-year CAREER grant, the PI proposes to elucidate the first generalized mechanistic and thermodynamic framework governing the formation of single-walled metal oxide nanotubes and nanoshells, through a unique combination of materials synthesis, advanced liquid-phase and solid-state characterization tools, molecular simulation, and analytical theory. Towards the end of this period and in the longer term, he will apply this enabling framework to guide the engineering of new classes of nanoscopic objects that can impact a wider range of technologies pursued by diverse researchers and also impact current thinking in bottom-up nanotechnology based on oxide materials. This framework also has potential implications in understanding natural processes whose hypothesized mechanisms have several common features with his approach, such as the biomineralization of silica and other inorganic oxides, and the evolution of ordered objects (e.g., nanotubes, nanoshells, and proto-zeolites) in natural environments.
Broader Impacts: This career plan, along with infrastructure built by the PI in recent years, will effectively integrate research and education at multiple levels - from the high school student to the professor - and create long-term impact on a number of people. This CAREER grant will be a cornerstone of a partnership between Georgia Tech (GT) faculty and the Gwinnett School of Mathematics Science and Technology (GSMST), a STEM-focused charter high school. The PI, his graduate and undergraduate students, visiting students, GSMST teachers, and GT K-12 outreach experts will collaborate to develop a set of laboratory and classroom modules that will be integrated in novel high-school courses on Nanotechnology and Alternative Energy. This collaborative approach - under development via a pilot project - will expose a total of ~150 high school students per year to cutting-edge engineering and science learning; retain and encourage such students in pursuit of STEM careers; and create an enjoyable and productive experience for GT and GSMST participants with a level of activity that does not affect research productivity. The PI will translate the exciting research insights into the GT classroom by incorporating them into his undergraduate/graduate course in nanoscale chemical engineering. The project involves five GT undergraduates and five external students by collaboration with the NSF-SURE program which brings minority-group students to GT for research every summer. The results will be disseminated via publications and presentations, and also have continued potential for dissemination to the general public by the science and technology news media. Overall, this career plan is designed to help build a substantial cadre of well-trained personnel in technology and science research, education, and application; who can be readily absorbed by US industry (including the growing nanotechnology industry) and academia.
