Water and ion transport in ceramic carbon electrodes for fuel cells

聚合物电解质膜燃料电池（PEMFC）是一种清洁能源技术，它通过电化学反应氢和氧来产生水和电。PEMFC目前在工业车辆（例如叉车）和固定/备用电源等利基商业市场中变得有利可图。该技术可以更广泛地应用于能源领域，前提是可以改善材料的性能成本比。该提案的重点是研究和提高一种新的和创新的燃料电池电极技术，即磺化硅基陶瓷碳电极（SS-CCE）。SS-CCE使用低成本有机硅烷前体制备，所述有机硅烷前体与单体形式的镀铂碳（Pt/C）催化剂混合，随后在单个步骤中聚合并涂覆到气体扩散层上。与常规燃料电池材料相比，这些电极结构显示出优异的性能和对干燥操作条件的上级耐受性，常规燃料电池材料的性能如果没有很好地水合的话会受到严重影响。热/干操作的能力可以意味着加湿器系统消耗更少的寄生功率，这将导致显著的系统效率。这项战略资助的长期目标是了解使这些SS-CCE在干燥条件下表现良好的现象，并进一步提高材料的性能。这反过来又可以评估我们在炎热和干燥操作条件下的保水新策略-在每个催化剂层中放置吸湿添加剂，而不是用类似吸湿材料改性膜的传统方法。该项目将侧重于了解化学成分如何影响电极的电化学和物理性能。这沿着由SS-CCE制成的燃料电池的真实的世界测试耐久性测量将使得能够评估我们的高温/低相对湿度燃料电池操作的新方法。预计该项目的成果将导致开发性能更高、成本更低的燃料电池，使加拿大能够满足其清洁能源需求。

Polymer electrolyte membrane fuel cells (PEMFC) are a clean energy technology that electrochemically reacts hydrogen and oxygen to produce water and electricity. PEMFCs are currently becoming profitable in niche commercial markets such as industrial vehicles (e.g. forklifts), and stationary/backup power. The technology could be more widely deployed in the energy landscape provided that improvements can be made in the performance-to-cost ratio of the materials. This proposal is focused on the study and enhancement of a new and innovative fuel cell electrode technology, namely sulfonated silica-based ceramic carbon electrodes (SS-CCE). SS-CCE's are prepared using low-cost organosilane precursors that are mixed with the platinized carbon (Pt/C) catalyst in monomer form, and subsequently polymerized and coated onto a gas diffusion layer in a single step. These electrode structures display excellent performance and superior tolerance to dry operating conditions compared to conventional fuel cell materials, whose performance suffers severely if not well hydrated. The ability to operate hot/dry could leave means less parasitic power is consumed by humidifier systems which would lead to substantial system efficiency. The long term objective of this strategic grant is aimed at understanding the phenomena that enable these SS-CCEs to perform well under dry conditions, and to further improve the material's performance. This will in turn allow evaluation of our new strategy for water retention under hot and dry operating conditions - locating hygroscopic additives in each catalyst layer, as opposed to the conventional approach of modifying the membrane with similar hygroscopic materials. This project will focus on understanding how the chemical composition influences the electrochemical and physical properties of the electrodes. This, along with real world testing durability measurements of fuel cells made from SS-CCEs will enable the evaluation of our novel approach to high temperature/low relative humidity fuel cell operation. It is expected that the results from this project will lead to the development of higher-performing and lower-cost fuel cells, which will enable Canada to meet its clean energy needs.