杂原子掺杂层次孔炭氧还原电催化剂的组成、结构优化及相关基础研究

The appearance of non-metal hetero-atom doped carbon materials provide a new approach for the development of novel highly efficient and low-cost electrocatalysts for oxygen reduction reaction. In order to further enhance the electrocatalytic performance of hetero-atom doped carbon materials, the fundametal issues including constructure of their microscopic structure, adjustment of the surface components and electronic structure, and the electrocatalytic mechanism etc. should be further systematically investigated. The present proposal aims to prepare novel hetero-atom doped hierarchical porous carbon materials with both macropores for shortering the mass transfer distance and mesopores for benefiting the transfer of mass and charge through combining the in-siu polymerization and template method. Their morphology and pore configuration will be regulated and controlled by adjusting the template structure and the operation parameter of in-situ polymerization technology. The surface defects and electronic structure of the doped hierarchical porous carbon materials will be regulated by co-doping different hetero-atoms. Furthermore, the cheimcal configuration of the hetero-atoms will be adjusted by chosing different precursors of hetero-atoms and controlling the technology of both polymerization and carbonization.The electrocatalytic performance of oxygen reduction reaction will be evaluated on different hetero-atom co-doped hierarchical carbon porous materials and their supported catalysts. Based on the above investigation, their electrocatalytic mechanism for oxygen reduction reaction will be revealed and their corresponding “structure-activity” relationship will be discussed and investigated. This project will provide a useful theoretical reserve and experimental accumulation for the non-metal hetero-atom doped carbon materials, and thus promote the industrialization process of fuel cells, which is of vital importance.

非金属杂原子掺杂炭材料的出现，为开发新型高效、廉价的氧还原电催化剂提供了一个新途径。要进一步提高杂原子掺杂炭材料的电催化性能，需要对其微尺度结构构筑、表面组分与电子结构调控、催化作用机制等基础问题展开进一步系统的研究工作。本项目拟采用原位聚合-模板法制备兼具大孔（缩短反应物传输距离）和介孔（利于物质和电荷传输）结构的新型杂原子掺杂层次孔炭材料；通过调整模板结构和原位聚合工艺对材料的形貌、孔结构进行调控；通过多杂原子共掺杂，调控其表面缺陷与电子结构；通过选择杂原子前驱体种类，控制聚合和炭化工艺对杂原子化学构型进行调控。研究不同组成和结构的非金属掺杂层次孔炭材料及其负载型催化剂的氧还原电催化特性，揭示催化作用机制，探讨结构和性能之间的“构～效”关系。本项目的开展，为非金属杂原子掺杂炭氧还原电催化剂的研发提供有益的理论贮备与实验积累，对促进燃料电池的产业化进程，具有重要意义。

氧还原反应（ORR）是燃料电池、金属空气电池等新型能源转换装置的关键反应，开发高效的非贵金属氧还原反应电催化材料具有重要意义。本项目围绕杂原子掺杂层次孔炭ORR催化剂的组成、结构设计与调控，电催化活性机制，以及微观有序一体化电极的设计和制备技术等方面开展了一系列研究工作，取得了一些有特色的研究成果：1）联用硬模板-原位聚合/浸渍填充-高温炭化技术，制备了高比表面积，高有序度的N/S共掺杂有序介孔炭（OMC）非金属催化剂并高效用于电催化ORR；2）开发了氨气原位活化技术，实现了三维互联层次孔N掺杂炭材料孔结构的精确调控和表面化学组成与杂原子N构型的同步优化，揭示了N掺杂非金属炭催化剂的ORR催化活性与其石墨氮含量具有正相关关系；3）利用OMC阵列的限域效应及高比表面积，可控制备了小粒径、高分散的Fe-N-C材料，并作为H2-O2质子交换膜燃料电池阴极ORR催化剂进行测试，呈现出优异的峰功率密度和稳定性，加快了燃料电池的产业化进程；4）联用硬模板-电泳-氨气活化-浸渍复合技术，原位构筑了兼具微孔/介孔/大孔的Fe-N-C催化剂的微观有序一体化电极，该电极ORR催化性能明显优于传统方法制备的电极，为有序一体化电极的设计提供了新思路；5）通过比较Fe-N-C催化剂中吡啶N和Fe-N两种活性位对酸碱介质中ORR活性的增强因子，揭示了Fe-N活性位提高ORR活性的效果在酸性介质中明显优于碱性介质，深化了Fe-N-C材料电催化ORR机理理论。.通过本项目的实施，完成了研究计划。已发表高水平SCI期刊论文21篇，会议论文5篇；授权专利2件、申请专利2件；培养研究生6名；赴国外进行学术交流2人次。