溢出桥梁的Volmer/Tafel过程,在低超电位下实现安培级电流密度的性演变反应
Huai Qin Fu1, Min Zhou2, Peng Fei Liu3
1Centre for Catalysis and Clean Energy, Gold Coast Campus, Griffith University, Gold Coast, QLD 4222, Australia.
Journal of the American Chemical Society
|March 18, 2022
概括
这项研究引入了一种新的Ni3S2/Cr2S3电催化剂,用于性水电解中的高效演变反应 (HER). 催化剂通过优化水分离和通过溢出形成高电流密度.
科学领域:
- 电化学
- 材料科学
- 催化剂
背景情况:
- 通过性水电解进行工业化生产需要高效的电催化剂进行演化反应 (HER).
- 现有的HER电催化剂在高电流密度下难以保持性能,原因包括高覆盖率和低超电位.
- 开发能够在安培级电流密度下有效工作的催化剂对于实际应用至关重要.
研究的目的:
- 开发一种用于性水电解的新型电催化剂,能够在行业相关的安培级电流密度下工作.
- 阐明使高性能成为可能的机械路径,特别是解决水分离和形成问题.
- 在高电流密度下克服高覆盖面的局限性.
主要方法:
- Ni3S2和Cr2S3的协同混合,以创建双重活性位点.
- 研究反应机制的实验和理论研究,包括水吸附,解离和溢出.
- 电化学测量以评估催化剂的性能,重点是性介质中的电流密度和过量.
主要成果:
- 混合的Ni3S2/Cr2S3电催化剂促进了溢出桥的水分离和的形成.
- 催化剂有效地减轻了高覆盖抑制,并促进了Volmer/Tafel反应途径.
- 在1.0M KOH中,在251 ± 3 mV的低超电位下,达到3.5 A cm-2的高电流密度.
结论:
- Ni3S2/Cr2S3电催化剂在高电流密度下表现出演变反应的特殊性能.
- 协同效应和溢出机制是克服性水电解性能限制的关键.
- 这项工作为设计用于大规模生产的先进电催化剂提供了有前途的策略.
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