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: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=496660
• 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.

质子交换膜燃料电池依靠碳载体催化剂来增加催化层的活性催化表面积(CLS)。这种CLS的耐用性是质子交换膜燃料电池开发和商业化的关键问题。尽管炭黑(CB)载体被广泛使用，但它会被电化学氧化成表面氧化物(也是由铂催化的)，最终在阴极上氧化成二氧化碳。随着载体被腐蚀，铂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化含量的碳材料，例如我们在过去几年开发和研究的碳纳米结构(CNS)。我们的结果表明，在加速腐蚀条件下，在相同的时间内，铂/碳纳米管失去了100%的性能，而铂/碳纳米管只损失了23%。(1)一系列以碳黑为载体的二元PTM合金(M=Co，Cr，Mn，Mo)的ORR动力学增强了3~5倍。同时，考虑到铂的成本因素，我们打算研究PTM/CNS的性能和稳定性。铂合金催化碳载体腐蚀的活性与铂金属的活性相比，PTM的长期溶解和团聚的速度，铂双金属纳米颗粒的微观结构和ORR的增强是将被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率和更高的孔容。其他研究报告说，孔径较小的碳载体优先保留气相中的水，并减轻阴极CL内的泛滥。有必要对我们的CNS性质进行更详细的研究，以便在保留所有作为持久载体的基本特征的同时，对其孔几何结构进行有利的修改。(3)有序共振腔的模拟结果表明，如果化学发光具有与膜垂直的结构排列，可以获得更高的功率密度。因此，我们的最后一个目标是在墨水形式下通过施加磁场来施加铂/碳纳米管的优选取向。