高效碳点的合成及其在生物成像和光电材料中的应用

Carbon dots (CDs), such as polymer dots (PDs), graphene quantum dots (GQDs) and carbon nanodots (CNDs) possess exceptional advantages such as high chemical stability, low toxicity, fine compatibility and high quantum yield. These superiorities in CDs distinguish themselves from traditional fluorescent materials, making them perfect candidates for numerous exciting applications: bioimaging, medical diagnosis, photoelectric device, etc. In this project, first of all, aqueous-phase based methods will be developed to prepare these kinds of CDs. The relationship between photoluminescence (PL) of CDs and quantum size effect/molecule state emission/surface defect/chemical modification will be investigated in detail. Further, novel CDs with controlled structures/PL and multidimensional hybrids will be exploited. Secondly, the high quantum yield and fluorescent stability will be achieved through surface passivating and chemical modifying polymer chains of CDs, which will be beneficial to solve the compatibility between CDs and hydrophilic/ hydrophobic polymers. Furthermore, the successful compositing and hybridization CDs and functional polymers will be extended to luminescent, field effect transistor and photovoltaic device. Finally, through combining the specific biomolecules or activating groups on CDs, the modified CDs will possess specific effect on living cells, virus and other biological elements, and the following bio-labeling and imaging will be achieved.

聚合物点、石墨烯量子点、碳纳米点等碳类荧光点具有优异的化学稳定性，较低的毒性、良好的生物相容性及较高的量子产率等特点，在生物标记与成像，光学/光电材料与器件等方面有着重要的应用前景。本课题拟采用水相合成路线制备上述高效荧光碳点，探讨荧光性质与量子尺寸效应、分子态发光、表面缺陷和化学修饰的关系等荧光机理，进一步指导合成结构可控的多功能性新型碳点；通过表面钝化和修饰聚合物短链来改变发光颜色，提高量子效率和荧光稳定性，解决此类水溶性荧光碳点与亲水/疏水性聚合物的相容性问题，实现二者的复合与杂化用于发光、场效应晶体管及光伏器件方面；拟在碳点表面进行化学修饰引入能与细胞、病毒及其他生物基元表面产生相互作用的生物分子或基团，通过特定识别实现其生物标记与成像方面的应用。

碳点（包括聚合物点、石墨烯量子点、碳纳米点）具有优异的化学稳定性、较低的毒性、良好的生物相容性及较高的量子产率等特点，在生物标记与成像， 光学/光电材料与器件等方面有着重要的应用前景。本项目采用水相合成路线制备高效荧光碳点，探讨了碳点的量子尺寸效应、边缘态发光机理，并首次提出了碳点的分子态、碳核态及交联增强发射（CEE）的荧光机理；通过原料设计、反应条件优化以及后化学处理探究了带有带有特定结构和发光颜色碳点的可控合成；通过解决与聚合物的杂化相容性问题，实现了碳点在发光二极管中的高性能应用；利用碳点的表面多基团特性，实现了碳点作为太阳能电池的修饰层应用；利用碳点优异的荧光性质，通过原料设计、表面修饰，开发了碳点在特异性抗菌、（特异性）生物成像等方面的应用。