组合电化学:一种高度并行的光学选方法,用于发现更好的电催化剂
1T. E. Mallouk, E. Reddington, A. Sapienza, Department of Chemistry, The Pennsylvania State University, University Park, PA 16802, USA. E. S. Smotkin, B. Gurau, R. Viswanathan, Department of Chemical and Environmental Engineering, Illinois Institute.
概括
一种新的光成像方法有效地选电化学催化剂. 这项技术确定了用于直接甲醇燃料电池的高度活性,,和的组合.
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
- 催化剂是一种催化剂.
背景情况:
- 对于大样本集,用于选电化学催化剂的电流电压方法是低效的.
- 开发新型催化剂对于推进直接甲醇燃料电池等能源技术至关重要.
研究的目的:
- 开发和应用基于光的方法,用于电化学催化剂的高通量选.
- 确定用于甲醇电氧化的高活性催化剂组合物.
主要方法:
- 使用光成像技术,将离子产物转换为视觉信号.
- 采用了645个成员的电极阵列,包括Pt,Ru,Os,Ir和Rh的二进制,三进制和四进制组合.
- 进行"放大"屏幕,以确定最佳的催化剂组成.
主要成果:
- 使用光成像识别了高活性催化剂组合物.
- 发现了高级三元和四元催化剂,其中一些位于较不活跃的二元组合之间.
- 最好的催化剂Pt44) / Ru41) / Os10 / Ir5在60°C的直接甲醇燃料电池中表现优于Pt50 / Ru50尽管表面积较小.
结论:
- 基于光的选是一种有效的方法来识别先进的电化学催化剂.
- 多元素催化剂组合,特别是三元和四元,可显著提高性能.
- 这种方法加速了对直接甲醇燃料电池的有效催化剂的发现.
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