导电聚合物微纳米结构与界面浸润性协同调控的高效氧还原反应

The sluggish kinetics for the oxygen reduction reaction (ORR) and the high-cost of Pt-based catalysts inhibits the practical commercialization of fuel cells and metal-air batteries. The heterocyclic conjugated polymers, including polyaniline, polypyrrole, poly(3,4-ethylenedioxythiophene) (PEDOT), have recently been investigated as inexpensive non-precious-metal ORR electro-catalysts due to their low cost, high electronic conductivity, and distinct redox properties. However, there is no clear consensus on the understanding of the active site structures and catalytic mechanism, and there are still some challenges with respect to both ORR active and stability. Herein, our main goal is to research the synergistic effect between micro/nanostructured conducing polymers and their interfacial wettabillty for highly efficient ORR. The project on M-Yx-CP catalysts for ORR activity and stability will be proposed as follows: to design and fabricate the transition metals macrocycles compound-doped conducting polymer micro/nanostructures (M-Yx-CP) with multi-active sites, to illuminate the relationship between the interfacial wettability and M-Yx-CP catalytic activity, to fully understand the synergistic mechanism of M-Yx-CP molecular structures, micro/nanostructures, interfacial wettability for improving ORR activity. The scientific significance of the project lies in the introducing the M-Yx dopant, the controlled interfacial wettability into micro/nanostructured conducting polymers for ORR active,and revealing the mechanism of ORR catalytic mechanism. It will provide a theoretical and practical guide for designing and developing non-precious metal CP electrocatalytsts.

阴极氧还原反应（ORR）的低反应速率和Pt基催化剂的高昂成本严重制约了燃料电池和金属空气电池的产业化发展进程。由于导电聚合物（CP）独特的分子结构和掺杂导电机制，以CP为原料的非贵金属氧还原催化剂成为了电催领域的研究热点，但是，它的氧还原催化活性有待改善，且对ORR的催化机制尚未达成共识。因此，本申请项目拟采用具有催化活性的过渡金属-杂原子（M-Yx）配合物为掺杂剂，自组装高效、三维微纳米结构的CP电催化剂（M-Yx-CP）；通过调整M-Yx-CP的界面浸润性改善氧还原性能；实现导电聚合物的主链和掺杂剂分子结构、微纳米结构和界面浸润性对ORR性能的协同改善，揭示其协同调控机理。本项目的创新点是：协同调控导电聚合物主链上的N或S和过渡金属-杂原子（M-Yx）活性位点和密度、微纳米结构和界面浸润性，开发低价、高效的CP电催化剂，这对燃料电池的产业化发展具有重要的科学意义和技术应用价值。

阴极氧还原反应（ORR）的缓慢动力学过程、低的能源转化效率以及商业Pt 基催化剂的高昂成本，严重制约了燃料电池和金属空气电池的规模化商业化发展进程。因此，本项目利用导电聚合物的主链含有的N、S原子与过渡金属离子配位，设计和开发了系列导电聚合物基纳米材料和杂原子掺杂碳材料。通过调节其微观结构和分子结构、以及电极浸润性，改善了阴极氧还原性能、电化学稳定性;揭示了N、S、P、Co、Fe的掺杂不仅改变了聚合物主链、碳骨架的电子结构，而且提供了高密度的活性缺陷位，它们共同促进了催化剂的氧还原活性和长期稳定性。当催化剂作为可充锌空电池的阴极电催化剂时，表现出了高的能量密度和优异的充放电稳定性，在电动汽车、电网储能等领域具有广泛的应用前景。.具有超浸润性的电极材料表现出独特的对界面电化学反应的调控行为，可显著改善界面的传质和电荷传递行为。我们通过调节电极材料的浸润性，首次在亲水电极上实现了高效的微生物胞外电子的传递，揭示了亲水和疏水电极与微生物胞外电子传递的作用机制，为开发高性能微生物燃料电池提供了新的思路。此外，利用导电聚合物基材料的多级微纳米结构和本证的导电性，开发了其在电化学能源存储、液滴输运、微波吸收等领域应用，拓展了导电聚合物基纳米材料应用的领域和范围。