Chemical Grafting, Exfoliation and Dynamics of One and Two-Dimensional Boron-Nitride Nanostructures

纳米技术的进步一直是创造新的生物医学应用、能源运输和储存系统、航空航天材料和太阳能转换的核心。这项研究探索了由氮化硼(BN)制成的新型纳米结构。石墨烯是一种纳米碳，其中碳原子的蜂窝排列形成了薄片。当石墨烯被无缝轧制时，它会形成碳纳米管，这是一种众所周知的材料。交替的硼和氮原子可以取代碳纳米管中的碳形成BN纳米结构，与其碳类似物相比，BN纳米结构是具有优异热稳定性的宽带隙半导体。莱斯大学的安吉尔·马蒂教授和马泰奥·帕斯夸里教授专注于这些特殊的差异，他们正在探索如何通过将化学基团附着到BN纳米结构的表面并通过监测它们在溶液中的运动来调整BN纳米结构的性质。这些信息可能使这些纳米结构组装成具有定制的物理、化学和机械性能的复杂系统。这项研究可能会加速绝缘膜、防腐和紫外光电子产品的发现和创新。马蒂教授和帕斯夸里教授通过新闻稿和YouTube视频向更广泛的社区传播他们的研究成果。他们通过接触高中生、大学生和研究生，特别关注代表性不足的群体，提供前沿纳米科学活动，如研讨会、讲座和暑期研究机会。研究团队通过路易斯·斯托克斯少数民族参与联盟(LSAMP)计划从波多黎各招募和指导本科生。LSAMP促进了对未被充分代表的学生进行前沿纳米科学研究的培训。在美国国家科学基金会化学部大分子、超分子和纳米化学计划的支持下，Marti教授和Pasqui教授正在研究BN纳米结构的基本挑战，如表面功能化、剥落、分散和成像。BN纳米结构通过在比卢普斯-伯奇条件下(液氨中的锂)产生的有机基团来功能化各种基团。研究了这些官能化结构在不同环境和溶剂中的性质。此外，还研究了BN材料在不同电荷和不同极性的表面活性剂中的分散性，以了解影响其在水溶液中分散的条件。使用特殊的荧光表面活性剂，用荧光显微镜研究了分散结构，以了解BN纳米管在溶液中的动力学。克服这些挑战提高了一维和二维BN纳米结构的化学和性质的基本知识。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Advances in nanotechnology have been central to the creation of novel biomedical applications, energy transport and storage systems, aerospace materials, and solar energy conversion. This research explores novel nanostructures made of boron nitride (BN). Graphene is one type of nanocarbon in which a honeycomb arrangement of carbon atoms forms a thin sheet. When graphene is seamlessly rolled, it forms carbon nanotubes, a well-known material. Alternating boron and nitrogen atoms can replace carbon in carbon nanotubes to form BN nanostructures, BN nanostructures are wide band gap semiconductors with outstanding thermal stability, in contrast to their carbon analogs. Concentrating on these special differences, Professors Angel Marti and Matteo Pasquali of Rice University, are exploring how to tune the properties of BN nanostructures by attaching chemical groups to their surfaces and by monitoring their movements in solution. This information may enable the assembly of these nanostructures into sophisticated systems with tailored physical, chemical, and mechanical properties. This research may accelerate discovery and innovation in producing insulating films, corrosion protections, and UV optoelectronics. Professors Marti and Pasquali disseminate their research to the greater community through press releases and YouTube videos. They provide cutting-edge nanoscience activities such as workshops, talks, and summer research opportunities by reaching out to high school, college, and graduate students, paying particular attention to underrepresented groups. The research team recruits and mentors undergraduate students from Puerto Rico via the Louis Stokes Alliances for Minority Participation (LSAMP) Program. LSAMP facilitates the training of underrepresented students in cutting-edge nanoscience research. Supported by the Macromolecular, Supramolecular and Nanochemistry Program of NSF's Chemistry Division, Professors Marti and Pasquali are addressing fundamental challenges of BN nanostructures such as surface functionalization, exfoliation, dispersion, and imaging. BN nanostructures are functionalized with a variety of groups by virtue of organic radicals produced under Billups-Birch conditions (lithium in liquid ammonia). The properties of these functionalized structures are studied in different environments and solvents. Furthermore, the dispersibility of BN materials are studied in surfactants having different charges and polarities to understand the conditions that lead to their dispersion in aqueous solution. Dispersed structures are studied by fluorescence microscopy, using special fluorescent surfactants, to understand the dynamics of the BN nanotubes in solution. Overcoming these challenges advances fundamental knowledge of the chemistry and properties of one- and two-dimensional BN nanostructures.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.