New nanostructured carbon material as catalyst support for PEMFC-applicatioon

新型纳米结构碳材料作为 PEMFC 应用的催化剂载体

• 批准号: 238236-2009
• 负责人: Hamelin, Jean
• 金额: $ 1.46万
• 依托单位: Université du Québec à Trois-Rivières
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2013
• 资助国家: 加拿大
• 起止时间: 2013-01-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=524254
• 关键词: New; nanostructured; carbon; material; catalyst

PEMFCs rely on carbon-supported catalysts to multiply the active catalytic surface area in the catalyst layers (CLs). The durability of such CLs is a crucial issue in PEMFCs development and commercialization. Despite its widespread use, the carbon black (CB) support undergoes electrochemical oxidation to surface oxides (also catalyzed by Pt) and eventually to CO2 at the cathode. As the support gets corroded away, Pt nanoparticules are lost from the electrode or aggregated to larger particles. One strategy is to use a carbon material with a higher graphitic content, such as the carbon nanostructures (CNS) that we have developed and studied for the past few years. Our results have shown that under accelerated corrosion conditions, for the same period of time by which Pt/CB lost 100% of its performance, Pt/CNS had only lost 23%. Our research proposal is in continuity with what we have accomplished so far and has three objectives: (1) A series of binary PtM alloys (M = Co, Cr, Mn, Mo) supported on CB have shown some enhancement in the kinetics of ORR by a factor of 3 to 5. Also, taking into account the cost consideration of Pt, we intend to study the performance and stability of PtM/CNS. The activity of the Pt alloy catalyzing the corrosion of carbon support compared with the activity of Pt metal, the rate of dissolution and agglomeration of PtM over long runs, the microstructure of Pt-bimetallic nanoparticules and ORR enhancement are some of the key areas that will be covered. (2) Another important aspect of our CNS is their enhanced micro porosity and higher pore volume. Other studies reported that carbon support with smaller pore sizes preferentially retains water in the gas phase and alleviates flooding within the cathode CL. A more detailed investigation of our CNS properties is necessary in order to induce favorable modifications in their pore geometry while retaining all the essential characteristics as a durable support. (3) Simulations with ordered CLs have shown that if the CL had a well defined structure alignment normal to the membrane, higher power densities could be achieved. Thus, our last objective is to impose a preferred orientation of the Pt/CNS by application of a magnetic field while in ink form.

PEMFC依靠碳载催化剂来增加催化剂层（CL）中的活性催化表面积。这种CL的耐久性是PEMFC开发和商业化的关键问题。尽管其广泛使用，但炭黑（CB）载体经历电化学氧化成表面氧化物（也由Pt催化）并最终在阴极处成CO2。随着载体被腐蚀掉，Pt纳米颗粒从电极上丢失或聚集成更大的颗粒。一种策略是使用具有更高石墨含量的碳材料，例如我们在过去几年中开发和研究的碳纳米结构（CNS）。我们的研究结果表明，在加速腐蚀条件下，在Pt/CB失去100%性能的相同时间段内，Pt/CNS仅损失23%。我们的研究计划与我们迄今为止所做的工作是连续的，并有三个目标：（1）一系列二元PtM合金（M = Co，Cr，Mn，Mo）负载在CB上显示出一定的ORR动力学增强3到5倍。此外，考虑到Pt的成本考虑，我们打算研究PtM/CNS的性能和稳定性。与Pt金属的活性相比，Pt合金催化碳载体腐蚀的活性、长时间运行的PtM的溶解和团聚速率、Pt-Pd纳米颗粒的微观结构和ORR增强是将涵盖的一些关键领域。(2)我们的CNS的另一个重要方面是其增强的微孔性和更高的孔体积。其他研究报道，具有较小孔径的碳载体优先将水保留在气相中，并在阴极CL内形成溢流。我们的CNS性能的更详细的调查是必要的，以诱导有利的修改，在其孔几何形状，同时保留所有的基本特征作为一个持久的支持。(3)有序CL的模拟表明，如果CL具有垂直于膜的明确定义的结构排列，则可以实现更高的功率密度。因此，我们的最后一个目标是施加一个优选的取向的Pt/CNS的磁场的应用，而在油墨形式。