Collaborative Research: Engineering the Morphology and Microstructure of Group III-V Compound Semiconducting Nanowires

加州大学洛杉矶分校和布朗大学的这项跨学科合作研究的目标是定量地了解控制III-V族化合物半导体纳米线异质结构生长的机制，从而开发出调整其形貌、结晶度和化学成分的策略。半导体纳米线由于其在光电子学、纳米电子学、传感器、能量采集和能量存储等方面的潜在应用，近年来受到了广泛的关注。然而，由于生长过程中存在动力学不稳定性，所需的多组分纳米线异质结构的生长是困难的。为了解决这个问题，拟议的研究将结合原位(以及非原位)纳米线生长随温度、时间、助熔剂和催化剂组成的函数的研究与理论/计算模型。然后将模拟的形貌和结构与实验观察进行比较，以定量描述纳米线生长过程中的形态、结构和成分的演变。如果成功，这项研究结果将提供对纳米线异质结构形成的整体理解，并有助于开发具有所需性能的先进功能材料的制造技术。所提出的实验和计算方法具有通用性，适用于研究(和预测)其他材料体系中纳米结构的生长以及其他合成(如溶液相)方法。结果将被公布，以加强对纳米线生长机制的理解。现场观察和生长模拟的视频将在网上发布，以促进公众对纳米科学和纳米技术的兴趣。研究生和工科本科生将从课堂教学和参与研究中受益。高中生将被邀请为他们提供第一手的研究经验，这将鼓励他们继续接受高等工程教育。

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