含氟石墨烯量子点的可控制备和性能研究

As one of novel zero-dimension carbon-based semiconductor nanomaterials, graphene quantum dots possess superiority in chemical inertness, biocompatibility, low toxicity, optical and electrical properties, and have a wide range of potential applications in the fields of in opto-electronics, catalysis, bioimaging and electrochemical sensors. However, the performance of graphene quantum dots-based organic opto-electronic devices is very poor due to their intrinsic high energy levels. To lower and finely tune the energy levels, this project is endeavored to introduce fluorine atoms with largest electronegativity and electron-withdrawing aromatic fluorine-containing building blocks into the framework of graphene quantum dots. Additionally, the project also aims to develop several facile and controllable preparation approaches of fluorine-containing graphene quantum dots materials, and produce a series of these materials with various fluorine loading amount, different types and distributions of fluorine-containing groups and building blocks via altering fluorinated agents and other conditions. Moreover, great efforts will be made to penetrate into the impacts of each structure factor on the basic properties. Through tailoring the energy levels and optimizing the properties, fluorine-containing graphene quantum dots materials may have great potential in solar cells, field effect transistor and catalysis applications.

石墨烯量子点是一种新型的零维半导体碳纳米材料，具有诸多优异性能，如化学稳定性、低毒性、生物相容性及独特的光电特性等，在光电子器件、催化、生物成像、电化学传感等领域拥有诱人的应用前景。然而，由于其固有的能级较高，使基于石墨烯量子点的光电器件性能很差。本项目致力于在石墨烯量子点骨架中引入电负性最大的氟原子及吸电子的含氟砌块，从而降低并精细地调控其能级。通过本项目的研究，我们将发展一些简单而有效的含氟石墨烯量子点的可控合成方法，制备一系列不同含氟量、含氟基团类型及区域分布不同的石墨烯量子点材料，并系统地研究各个因素对其光电性能的影响规律，以便有效地调节石墨烯量子点的能级、电学性能等，进一步开发含氟石墨烯量子点在太阳能电池、场效应晶体管、催化等领域的潜在应用。

作为结构独特的零维和二维的炭质材料，石墨烯量子点和石墨烯在聚合物太阳能电池中有着广泛的应用前景。针对目前常用的富勒烯型太阳能电池受体材料价格昂贵、不易获得的缺点，本项目开发了一种新型的含氟石墨烯量子点材料，将其作为富勒烯的替代材料应用于太阳能电池中，基于含氟石墨烯量子点的电池性能接近于富勒烯基的电池性能。聚合物太阳能电池常用的空穴传输材料是PEDOT:PSS，因其酸度高、易吸湿性，导致电池的稳定性较差。针对这些问题，我们开发了一种二维石墨烯磺酸材料，由于其酸性较小、耐湿性更好，基于石墨烯磺酸空穴传输层的太阳能电池不仅具有高于PEDOT:PSS电池器件的能量转换效率，而且还表现出更高的空气环境中的稳定性和热稳定性。针对聚合物太阳能电池常用的ITO透明阳极价格昂贵、易脆裂、不耐弯折等缺点，我们开发了一种价格低廉的石墨烯/铜纳米线复合透明导电材料。石墨烯/铜纳米线复合透明电极具有与ITO相当的面电阻和透光率，而且还表现出优异的耐高温高湿性和机械柔韧性。此外，我们还开发了一种廉价的无金属的石墨烯基电催化性，不仅比商品化的Pt/C贵金属催化剂具有更高的电催化活性，而且还表现出更好的抗甲醇毒性和循环稳定性。