The goal of this interdisciplinary collaborative research effort between UCLA and Brown University is to quantitatively understand the mechanisms governing the growth of group III-V compound semiconducting nanowire heterostructures and hence develop strategies to tailor their morphology, crystallinity, and chemistry. Semiconducting nanowires have recently gained considerable attention owing to their potential for applications in optoelectronics, nanoelectronics, sensors, energy harvesting, and energy storage. However, growth of desired multi-component nanowire heterostructures is difficult due to kinetic instabilities occurring during growth. To address this issue, the proposed research will combine in situ (as well as ex situ) studies of nanowire growth as a function of temperature, time, flux, and catalyst composition with theoretical/computational modeling. Simulated morphologies and structures will then be compared with experimental observations to quantitatively describe the morphological, structural, and compositional evolution during the growth of nanowires.
If successful, the results of this research will provide a holistic understanding of the nanowire heterostructure formation and help develop technologies for the fabrication of advanced functional materials with desired properties. The proposed experimental and computational methods are general and applicable to investigate (and predict) nanostructure growth in other material systems as well as other synthesis (eg., solution phase) methods. The results will be disseminated to enhance the understanding of the nanowire growth mechanisms. Videos of in situ observations and growth simulations will be posted on the Web to promote interest in nanoscience and nanotechnology among the public. Graduate and engineering undergraduate students will benefit through classroom instruction and involvement in the research. High-school students will be engaged to provide them firsthand research experience that will encourage them to pursue higher education in engineering
