苝衍生物/石墨烯自组装体衍生的纳米碳的结构调控及其电催化性能研究

Due to the fact that the oxygen reduction reaction (ORR) electrocatalysts are one of the key materials for fuel cell and oxygen sensor, the rational design of the ORR electrocatalysts with high performance is of theoretic and realistic significance. Recent progress on the intrinsic origin of the catalytic activity of carbon-based electrocatalysts has been made, and it is necessary to further improve the catalytic activity by finely tuning the microstructure of electrocatalysts. In this project, we will focus on the structural tailoring and electrocatalytic performance of nanocarbons derived from integrated assembiles of perylene derivatives/graphene. Graphene or graphene oxide will be acted as the model substrate to direct the self-assembly of a versatile organic molecules, perylene derivatives into various functional nanostructures through π-π interactions between graphene and perylene derivatives. After deliberate calcinations at high temperature, thus-prepared graphene integrated supramolecular nanocomposites will be transformed into the carbon-based metal free materials with various carbon defects on the graphene nanosheets. The electrocatalytic activities of the above carbon-based materials will be investigated for oxygen reduction reaction, and the relationship between electrocatalytic behaviours and the fine structures of carbon-based electrocatalysts will be revealed. It is expected that nano-structured carbon based electrocatalysts with high activity will be developed, which will strongly support the development of fuel cells and oxygen sensors in the future.

氧还原反应催化剂是燃料电池和氧气传感器的关键材料之一，理性设计高性能氧还原电催化剂具有重要科学意义和实用价值。近期针对碳基材料电催化活性起源的认识取得了一定进展，非常有必要通过精细设计碳基催化剂的缺陷结构，进一步提高此类材料的电催化性能。本项目主要研究苝衍生物/石墨烯自组装体衍生的纳米碳材料的结构调控及其对氧还原反应电催化性能的影响。基于石墨烯与苝衍生物之间独特的pi-pi相互作用，通过采用不同氧化程度的石墨烯，诱导并控制不同苝衍生物在石墨烯表面的生长，进而调控苝衍生物/石墨烯自组装体经高温煅烧后所获得碳材料中的缺陷结构，通过考察并比较上述碳材料对氧还原反应电催化性能的差异，揭示纳米碳基催化剂的微结构与电催化性能之间的影响规律，进而开发出具有高活性的纳米碳基电催化剂，相信此类电催化体系的开发将为未来燃料电池及氧传感器技术的发展提供有力支持。

氧还原反应催化剂是燃料电池的关键材料之一，理性设计高性能氧还原电催化剂具有重要科学意义和实用价值。近期针对碳基材料电催化活性起源的认识取得了一定进展，有必要通过精细设计碳基催化剂的缺陷结构，进一步提高其电催化性能。本项目主要发展了一系列苝衍生物/石墨烯自组装体衍生的纳米碳材料和以其为基底负载过渡金属催化剂材料，通过精心调控催化材料的精细结构，实现了催化氧还原性能的提高优化，取得了如下重要进展：首先，利用石墨烯与苝衍生物之间独特pi-pi相互作用，调控组装参数，实现了苝四羧酸在氧化石墨烯上的长大，随后采用高温煅烧得到了不同结构的碳纳米点修饰石墨烯的氧还原催化剂，展现出优异的催化活性和抗甲醇毒化能力。在此基础上，成功构筑了富缺陷碳层包裹的过渡金属催化剂，通过对富缺陷碳层的调控，实现了催化剂活性和稳定性的最大化，研究了碳层和过渡金属原子之间的相互影响关系（如电子和几何效应），分析了催化剂表面原子的电子结构改变对催化活性的影响。通过考察并比较上述碳材料对氧还原反应电催化性能的差异，揭示了纳米碳基催化剂的微结构与电催化性能之间的影响规律，为构建未来新型低成本电催化剂提供了一定的理论基础和新思路。