Department of Mechanical and Aerospace Engineering, University at buffalo, The State University of New York, Buffalo, NY 14260, USA.
Nanoscale. 2019 Mar 21;11(12):5640-5645. doi: 10.1039/c8nr10373a.
The selective detection of molecules with less energy consumption depends critically on novel sensing concepts and the emergence of new sensor materials. Excitons and dipole moments are two strongly correlated states that have shown coupled electronic interactions on the nanoscale, and they are highly sensitive to changes in their surroundings. Here, we present exciton-dipole coupling in the two-dimensional (2D) assembly of molecular rubrene excitonic crystals to selectively detect molecules. The presence of molecules with a dipole moment transforms excitons into charge transfer, resulting in a pronounced conductivity change of freestanding rubrene nanosheets. The exciton-dipole coupling exhibits highly efficient molecular selectivity, as it offers an unambiguous electronic fingerprint for the detection of molecules - in contrast to common sensing schemes relying on the quantification of intensity changes and optical peak shifts.
分子的低能耗选择性检测在很大程度上取决于新颖的传感概念和新型传感器材料的出现。激子和偶极矩是两种紧密相关的状态，它们在纳米尺度上表现出耦合的电子相互作用，并且对周围环境的变化非常敏感。在这里，我们在分子并五苯激子晶体的二维（2D）组装中展示了激子-偶极耦合，以选择性地检测分子。具有偶极矩的分子的存在将激子转化为电荷转移，导致游离并五苯纳米片的电导率发生明显变化。激子-偶极耦合表现出高效的分子选择性，因为它为分子的检测提供了明确的电子指纹，与依赖于强度变化和光学峰位移的定量的常见传感方案形成对比。
