有机自由基磁性材料一维微/纳结构中的电荷输运和磁场调控

Organic spintronics is a very young interdiscipline, which is still in its early stage. It is a field that needs large effort in both materials development and device fabrication. On the one hand, organic materials used in organic spintronic devices are mainly Alq3 and oligomeric thiophenes, lacking diversity and novelty. On the other hand, though many novel spintronic devices are designed, some of them are still concepts. Moveover, large magnetoresistance of most spintronic devices could only be realized at low temperature, which limits their application in real life. Therefore, the development of organic spintronics needs to investigate more novel organic materials to accumulate the experimental data, summarize the law and build the theoretical model. This project aims to develop a facile and efficient methodology to synthesize novel organic radical materials with nitronyl nitroxide radicals bonded to organic π-conjugated molecules that have high carrier mobility. The investigation will enrich the materials for the investigation of organic spintronics. In addition, this project proposes for the first time to modulate the performance of the field-effect transistors based on one-dimensional micro/nano-structures formed by the organic radical magnetic materials by magnetic field. Modulating the charge transport of organic semiconductors by both electric field and magnetic field provides new ideas on the development of subminiature multi-functional and multi-responsive organic memory devices and chemistry sensors.

有机自旋电子学作为一门新兴的学科，尚处在起步阶段。材料方面的结构单一。尽管诸多新颖的器件结构被提出来，但是很多器件结构仍处在概念性阶段。而且许多有机自旋电子学器件只能在低温下实现大的磁致电阻，无法在室温下操作。因此，有机自旋电子学领域急需合成大量具有新颖结构的材料，积累实验数据，总结规律，建立模型。本项目提出将氮氧自由基引入有机π共轭分子，发展简捷高效的合成方法学，通过将高迁移率的有机π共轭分子与氮氧自由基偶联起来，为新材料的发展提供高效的合成方法，并丰富有机自旋电子学的研究对象，并首次提出利用磁场调控基于一维有机自由基磁性材料微/纳结构的场效应晶体管器件，实现电场和磁场对有机半导体材料载流子传输的双调控，为开发微型多功能多响应有机存储器件及化学传感器件提供了新的思路。

本项目围绕发展新型有机自由基磁性材料并研究其微纳结构中的电荷输运和磁场调控这一总体目标开展了一系列研究。主要研究内容包括：（1）新型有机共轭分子骨架的设计、合成及其微纳结构研究；（2）含有机自由基的共轭分子骨架的设计、合成与性能研究。发展了一批高迁移率新型共轭骨架结构，探索了共轭骨架上引入有机自由基基团后材料的稳定性及磁学性质，获得了具有高稳定性的压力响应型有机自由基材料，为下一步工作的深入开展奠定了基础。共发表SCI收录论文30篇，其中包括J. Am. Chem. Soc. 4篇，Adv. Funct. Mater. 2篇，Chem. Mater. 2篇，Chem. Sci. 2篇，另有两篇工作准备投稿。