厦门大学洪文晶团队报道了超分子自由基电子工程。相关研究成果发表在2023年7月26日出版的《美国化学会杂志》。

超分子自由基化学是连接超分子化学和自由基化学的一个新兴领域，将自由基整合到超分子结构中为调节其结构和功能提供了一个新的维度。尽管人们已经致力于超分子结的制备，但由于在单分子水平上产生超分子自由基的挑战，通过超分子自由基进行的电荷传输表征仍未得到探索。

该文中，研究人员使用基于电化学扫描隧道显微镜的断裂结（EC-STM-BJ）技术展示了超分子自由基结的制备和电荷传输研究。研究发现，超分子自由基连接的电导率比没有自由基的超分子连接高出1个数量级以上，甚至比具有相似长度的完全共轭的低聚苯二胺分子的电导率高。实验和理论相结合的研究表明，自由基增加了超分子自由基连接处的结合能，减小了能隙，从而导致通过超分子自由基的近共振传输。

研究工作表明，超分子自由基不仅可以在构建块之间提供强结合，还可以提供有效的电耦合，这为超分子自由基化学和具有超分子自由基的新材料提供了新的见解。

附：英文原文

Title: Supramolecular Radical Electronics

Author: Tengyang Gao, Abdalghani Daaoub, Zhichao Pan, Yong Hu, Saisai Yuan, Yaoguang Li, Gang Dong, Ruiyun Huang, Junyang Liu, Sara Sangtarash, Jia Shi, Yang Yang, Hatef Sadeghi, Wenjing Hong

Issue&Volume: July 26, 2023

Abstract: Supramolecular radical chemistry is an emerging area bridging supramolecular chemistry and radical chemistry, and the integration of radicals into the supramolecular architecture offers a new dimension for tuning their structures and functions. Although various efforts have been devoted to the fabrication of supramolecular junctions, the charge transport characterization through the supramolecular radicals remained unexplored due to the challenges in creating supramolecular radicals at the single-molecule level. Here, we demonstrate the fabrication and charge transport investigation of a supramolecular radical junction using the electrochemical scanning tunneling microscope-based break junction (EC-STM-BJ) technique. We found that the conductance of a supramolecular radical junction was more than 1 order of magnitude higher than that of a supramolecular junction without a radical and even higher than that of a fully conjugated oligophenylenediamine molecule with a similar length. The combined experimental and theoretical investigations revealed that the radical increased the binding energy and decreased the energy gap in the supramolecular radical junction, which leads to the near-resonant transport through the supramolecular radical. Our work demonstrated that the supramolecular radical can provide not only strong binding but also efficient electrical coupling between building blocks, which provides new insights into supramolecular radical chemistry and new materials with supramolecular radicals.

DOI: 10.1021/jacs.3c04323

Source: https://pubs.acs.org/doi/10.1021/jacs.3c04323