新型富酚电极的设计合成与超级电容器储能性能

Firstly, the project will design and synthesize the guest molecules for covalent modifications. The aniline molecule is used as a core to obtain the rich-phenol molecular scaffolds by forming the bonds between dihydroxyphenyl and aniline which can bear more Faraday charges (the rich-phenol molecular scaffold is able to achieve the theoretic specific capacitance of 1318 F g-1 in the potential range of 1.0 V). Following this idea, the other electrochemically active groups can be selected to connect to the aniline core according to the desired potential range of the positive and negative electrodes. Secondly, the MWCNTs will be transversely cut and longitudinally unzipped, resulting in the formation of allotrope graphene nanoribbon /fragmentary carbon nanotube. In addition, the reduced graphene oxide nanosheets are used to prepare the porous graphene nanosheets by means of reoxidation. The two kinds of carbon-based materials will be acted as a host for modifications. Thirdly, the covalent grafting of the resultant molecular scaffold directly on the carbon network can been accomplished with the corresponding diazonium salts. As a result, the so-called rich-phenol electrode material is prepared. Finally, the conventional or flexible device will be assembled by matching the potential of positive electrode with negative electrode and selecting appropriate electrolytes and voltage windows on basis of the experimental results. Furthermore, the project will explore or evaluate the issue concerning with the investigation, such as synthesis strategies, mechanisms and active sites related to the reaction of diazonium salt, kinetics of electrode reaction with more than one electron, the comparative advantage of the as-prepared materials in pseudocapacitance, and the cycling stability. The efforts will devote to the environment friendly and high-performance supercapacitors for energy storage.

首先，对共价修饰的客体分子进行设计合成，以苯胺为核，通过与邻苯二酚基团化学键拼接生成富含多酚基的分子骨架体系，承载更高的Faraday 电荷存储量（在1.0 V电势窗口下，理论比电容约为1318 F g-1），并按照这种思路在苯胺核上连接其它的电活性基团，根据正负电极需求调整修饰分子的电势适应范围；其次，利用多壁碳纳米管纵横切割和还原氧化石墨烯二次氧化等途径分别制备主体碳基材料——石墨烯纳米带/残缺碳纳米管同素异形结构和多孔石墨烯片；随后，利用重氮化反应将合成的客体分子接枝到特定碳基质表面，形成所谓的富酚电极材料；最终，以此为基础选择适当的电解质体系和电位窗口，合理匹配正负极进行传统或柔性器件组装。对过程涉及的有机合成策略、重氮化接枝反应机理及其活性位点的形成途径、多电子复杂动力学行为、赝电容优势及循环稳定性等进行探索和评价，为实现性能优越且绿色环保的超级电容器储能装置提供理论和技术支撑。

在项目执行期间，我们通过有机合成策略、结构设计以及官能团优化等特殊的方法途径，获得了多种富含酚（或醌）官能团且具有电化学活性的有机分子骨架体系。在此基础上，借助化学共价和非共价修饰技术，将富酚分子键合到碳基质表面，制备合成了多达十几种新型的全碳、环保、可持续型电化学储能有机分子电极，并匹配组装成对称或非对称类商业储能装置，其能量密度通过改善有机分子电极的电化学储能性能、正负极合理匹配和拓宽电位窗口等方法得以提升。此外，沿着有机分子电极的思路对课题研究作了拓展，探索性地将电化学活性的蒽醌基团嵌入到共价有机框架（Covalent Organic Frameworks, COFs）分子结构单元，形成新型的富含酚基或醌基有机电化学储能材料。围绕课题所涉及的电化学过程中的相关科学问题，开展了多方面的探索和研究，取得了丰硕的研究成果，在国内外学术期刊上发表学术论文41篇。例如，J. Mater. Chem. A (2篇), Chemical Engineering Journal(1篇), Journal of Power Sources (1篇)、Journal of Physical Chemistry C(1篇)、 Electrochimica Acta (3篇)、Dalton Transactions(1篇) 、 Journal of Colloid and Interface Science (1篇)、Advanced Materials Interfaces（1篇）、Journal of Energy Storage（1篇）、ACS Applied Energy Materials（2篇）、Energy & Fuels（1篇）、International Journal of Hydrogen Energy(3篇)、Journal of Physics and Chemistry of Solids （1篇）、Journal of Alloys and Compounds (4篇)等。其中SCI期刊源论文39篇。申请国家发明专利4项，授权2项。此外，培养了11名硕士研究生和4名博士研究生。