GDE在CO中的稳定性2 电还原到格式:离子体类型和负载的作用
Jose Antonio Abarca1, Lucas Warmuth2, Alain Rieder3,4
1Departamento de Ingenierías Química y Biomolecular, Universidad de Cantabria, Avenida de los Castros s/n, Santander 39005, Spain.
概括
在气体扩散电极 (GDE) 中优化催化剂层组成,可以增强二氧化碳 (CO2) 的电化学减少以形成. 导离子离子体和PTFE添加剂提高了GDE的稳定性和脱碳的性能.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 电化学减少CO2 (ERCO2) 形成对于脱碳至关重要,但气体扩散电极 (GDE) 稳定性是一个主要障碍.
- 目前的GDE设计面临着由于催化剂层 (CL) 降解和低效的二氧化碳输送而带来的长期性能挑战.
研究的目的:
- 系统地研究催化剂层组成如何影响GDE性能和ERCO2形成的耐用性.
- 为了优化离子体选择,催化剂与离子体的比率,以及使用PTFE添加剂提高GDE稳定性的疏水性.
主要方法:
- 在GDE中对导质子 (Nafion) 和导离子 (Sustainion) 离子体进行比较分析.
- 优化催化剂与离子体的比率,并加入PTFE来调整催化剂层的疏水性.
- 在ERCO2条件下优化GDE的长期稳定性测试 (24小时).
主要成果:
- 基于Sustainion的GDE比基于Nafion的GDE更好地抑制了演化反应 (HER).
- 在这两种系统中,过度的离子体负荷导致孔隙堵塞,并降低了CO2的可访问性.
- 用PTFE修改的Sustainion GDEs实现了24小时连续运行,具有高格式选择性 (~85%) 并抑制了HER (<10%).
结论:
- 催化剂层的组成极大地影响了ERCO2中的GDE稳定性和性能.
- 导离子离子体和受控的疏水性 (通过PTFE) 是防止电解质泛滥和提高GDE耐用性的关键.
- 这项研究为可扩展的ERCO2提供了可行的策略,以形成技术.
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