Chemical Control of Quantum Defects in Low-Dimensional Carbon Materials

化学系的大分子、超分子和纳米化学(MSN)项目获得这一奖项，资助马里兰大学的王玉皇教授研究化学缺陷对线性和二维碳材料物理性质的影响。就像海洋中的岛屿一样，这些缺陷在原本平坦的表面上成为活动的焦点。这些点是有趣的新化学和物理可以出现的地方。这项拟议研究的成功完成可能会开启一种全新的工程材料方法，可以转化为光学探测器和选择性化学传感器的新条目。这项拟议的工作还计划通过研究生-本科生指导，吸引本科生，包括来自代表性不足群体的学生，直接参与研究计划。拟议的缺陷是在王教授的实验室里通过将受控数量的官能团共价连接到半导体碳纳米管模型系统上而合成的。这类缺陷的美丽之处在于其定义更明确的结构，出色的化学可调性，以及更重要的是，以前意想不到的荧光特性。激子或电子-空穴对可以在量子缺陷位置发光，从而有可能使用传统的光谱技术在实验上探测缺陷。这些化学定制的荧光量子缺陷将被探索为一种新的工具来设计纳米材料，潜在地打破纳米管光致发光的暗激子限制，并探测否则可能难以捕获的化学事件。

With this award, the Macromolecular, Supramolecular and Nanochemistry (MSN) program of the Division of Chemistry is funding Professor YuHuang Wang of the University of Maryland to investigate the effect of chemical defects on the physical properties of linear and two dimensional carbon materials. As with islands in the sea, these defects serve as focusing points of activity on an otherwise plain surface. These points are where interesting new chemistry and physics can occur. Successful completion of the proposed study may open an entirely new approach to engineering materials that could translate into new entries into optical probes and selective chemical sensors. The proposed work is also projected to engage undergraduate students, including students from underrepresented groups, directly in the research program through graduate-undergraduate mentorship.The proposed defects are being synthetically created in Prof. Wang's laboratory by covalently attaching a controlled number of functional groups to semiconducting carbon nanotube model systems. The beauty of this type of defect is its better-defined structure, excellent chemical tunability, and more importantly, previously unexpected fluorescent properties. An exciton, or electron-hole pair, can light up at the quantum defect site, making it possible to experimentally probe defects using conventional spectroscopic techniques. These chemically tailored, fluorescent quantum defects will be explored as a new tool to engineer nanomaterials, potentially to break the dark exciton limit of nanotube photoluminescence, and to probe chemical events that could be otherwise difficult to capture.