均质电催化剂的基准测试:超电位,周转频率,限制周转数
Cyrille Costentin1, Guillaume Passard1, Jean-Michel Savéant1
1Université Paris Diderot, Sorbonne Paris Cité, Laboratoire d'Electrochimie Moléculaire, Unité Mixte de Recherche Université - CNRS N° 7591, Bâtiment Lavoisier, 15 rue Jean de Baïf, 75205 Paris Cedex 13, France.
Journal of the American Chemical Society
|March 11, 2015
概括
新的方法对分子催化剂进行基准测试,以应对能源挑战. 这种方法通过使用催化剂Tafel图表和通过限制有效电解的周转数来评估催化剂稳定性的内在性能.
科学领域:
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
背景情况:
- 分子催化剂,特别是过渡金属复合物,对于通过小分子激活来应对当代能源挑战至关重要.
- 众多催化剂的快速发展需要标准化的基准测试工具.
研究的目的:
- 开发一个全面的框架,用于能源应用中的分子催化剂的基准测试.
- 引入和定义用于评估催化剂性能和稳定性的关键指标.
主要方法:
- 使用"催化塔菲尔图"来评估内在的催化性能,独立于电化学电池参数.
- 引入"限制周转数"以量化电解过程中的催化剂停用.
- 从电流,电荷和催化剂度测量中开发估计这些因素的程序.
主要成果:
- 催化剂表图提供了细胞独立的内在催化剂活性测量.
- 限制周转数量化催化剂稳定性和运行寿命.
- 分析揭示了内在性能和禁用如何共同控制电解结果.
结论:
- 结合催化剂Tafel图表和限制营业额的双重方法提供了强大的催化剂基准测试.
- 这些指标可以准确评估和比较用于能量转换的分子催化剂.
- 提出的方法方便合理设计和选择高效和稳定的电催化剂.
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