通过抑制网状氧气参与酸性水的氧化,稳定高度活跃的Ru站点
Yunzhou Wen1, Peining Chen1,2, Lu Wang3,4
1State Key Laboratory of Molecular Engineering of Polymers, Department of Macromolecular Science and Laboratory of Advanced Materials, Fudan University, Shanghai 200438, China.
Journal of the American Chemical Society
|April 23, 2021
概括
开发新的 Sr-Ru-Ir二氧化物显著提高了氧化演化反应 (OER) 的活性和稳定性. 这些催化剂抑制了网状氧气的参与,改善了水电解剂的长期性能.
科学领域:
- 电化学
- 材料科学
- 催化剂
背景情况:
- 氧化演化反应 (OER) 对通过水电解产生至关重要,但受到能量转换效率和催化剂稳定性的限制.
- 目前基于 (Ir) 的催化剂缺乏足够的活性,而基于 (Ru) 的催化剂由于晶格氧化机制 (LOM) 而降解,导致不稳定.
研究的目的:
- 在酸性介质中开发先进的电催化剂,用于质子交换膜水电解剂.
- 研究新型三元氧化物电催化剂增强稳定性的机制.
主要方法:
- 合成三级氧化物电催化剂
- 电化学测试以评估OER活动和长期稳定性.
- 用于机械研究的X射线吸收光谱 (XAS) 和18O同位素标记的在线质谱 (OMS).
主要成果:
- Sr-Ru-Irnary 氧化物具有较高的 OER 活性,在 10 mA cm-2 时只需要 190 mV 的超电位.
- 经过1500小时的运行,超电位保持在225mV以下.
- 机械研究证实了由于Ru-O-Ir相互作用而抑制的晶格氧参与,并确定了Ru位点的调制电子结构.
结论:
- 对于高活性和稳定的OER电催化剂来说,Sr-Ru-Irnary氧化物是一个有前途的解决方案.
- 通过定制的局部结构和电子调制来抑制LOM是改善催化剂耐用性的关键.
- 这些发现有助于开发高效,强大的清洁生产催化剂.
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