CAREER: Bifacial Cyclophanes for Solution-Phase Synthesis of Semiconducting Porous Nanoribbons

在化学系大分子，超分子和纳米化学（MSN）计划的支持下，乔治城大学的Nagarjuna Gavvalapalli教授设计并开发了自下而上合成半导体多孔纳米带（SPNR）的策略。Gavvalapalli教授的团队从自然界的β-折叠设计中受到启发，设计了新型单体，以实现自下而上合成SPNR，并控制其带宽度，电导率和孔径。SPNR联合收割机将半导体的晶体管特性与纳米孔的传感和筛选能力相结合。它们可以潜在地用于诸如高通量运输检测、感测疾病的多种生物标志物和能量转换等应用。该项目有助于培训，教育和激励不同的人群，包括来自科学服务不足社区的高中生，本科生和公众。Gavvalapalli教授开发并使用“超级英雄科学计划”来挖掘人们对超级英雄的兴趣和好奇心，以便轻松地与来自不同背景的更广泛的观众建立联系。与传统的固态纳米孔相比，有机SPNR具有几个优点，包括单原子厚度和调节孔径、形状和化学功能的合成适应性。然而，目前的自上而下的方法不适合于产生SPNR，其控制上述应用所需的纳米尺度和孔尺寸以及它们的化学和电子结构。Gavvalapalli教授小组的拟议工作为SPNR设计了新型结构单元单体，并开发了自下而上和溶液相合成SPNR的设计规则，控制了带和孔的尺寸以及它们的化学和电子结构。单体被设计成使得它们阻碍链间货车范德华相互作用并使SPNR可溶液加工。本研究的三个主要目标是：i）改变单体设计参数以生成可溶性线性聚合物，为SPNR的溶解性提供指导; ii）识别和控制线性聚合物的结构参数，这些参数在将其转化为SPNR中起关键作用;和iii）合成各种纳米尺度宽度，孔径，和电子性质，并研究它们对SPNR的物理和电子性质的影响。这项研究提供了迄今为止一直难以捉摸的纳米多孔膜。 该奖项反映了NSF的法定使命，通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

With support from the Macromolecular, Supramolecular and Nanochemistry (MSN) Program in the Division of Chemistry, Professor Nagarjuna Gavvalapalli at Georgetown University designs and develops strategies for bottom-up synthesis of semiconducting porous nano-ribbons (SPNRs). Inspired from the β-sheets design in nature, Professor Gavvalapalli’s group designs novel monomers to enable bottom-up synthesis of SPNRs with control over their ribbon width, conductivity and pore size. SPNRs combine the transistor properties of semiconductors with the sensing and sieving capabilities of nanopores. They can be potentially useful for applications such as high-throughput transport detection, sensing multiple biomarkers of a disease, and energy conversion. The project contributes toward training, educating, and inspiring a diverse group of people including high-school students from underserved communities in science, undergraduate students, and the public. Professor Gavvalapalli develops and uses a “Superhero Scienceplanation” program to tap into people’s interest in and curiosity for superheroes in order to easily connect with a broader audience from diverse backgrounds. Organic SPNRs have several advantages, including single-atom-thickness and synthetic amenability to tune pore size, shape, and chemical functionality compared to traditional solid-state nanopores. However, the current top-down approaches are not suitable for generating SPNRs with control over the nanoribbon and pore dimensions as well as their chemical and electronic structure that are desirable for the above-mentioned applications. The proposed work in Professor Gavvalapalli’s group designs novel building block monomers for SPNRs and develops design rules for bottom-up and solution-phase synthesis of SPNRs with control over the ribbon and pore dimensions as well as their chemical and electronic structure. The monomers are designed such that they hinder interchain van der Waals interactions and render solution processable SPNRs. The three main objectives of the research are focused on: i) varying the monomer design parameters to generate soluble linear-polymers that provide guidelines for SPNRs solubility; ii) identifying and controlling the linear-polymer structural parameters that play a key role in transforming them into SPNRs; and iii) synthesizing SPNRs of various nanoribbon width, pore size, and electronic nature and studying their impact on the photophysical and electronic properties of SPNRs. This research provides access to nanoporous membranes that have been elusive so far. The obtained SPNRs enable transformative changes to above-mentioned technologies and also pave the way to new technologies.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.