掌握催化剂的表面应变,以实现高效的电催化
Tianou He1,2, Weicong Wang1,2, Fenglei Shi3
1State Key Laboratory of Multiphase Flow in Power Engineering, Xi'an Jiaotong University, Xi'an, China.
Nature
|October 7, 2021
概括
使用纳米立方体的 (Pt) 催化剂的应变工程允许精确调整甲醇氧化和演化等反应的电催化活性.
科学领域:
- 材料科学
- 电化学
- 催化剂
背景情况:
- (Pt) 是可持续能源系统中的关键电催化剂,其活性受电子结构和晶格应变的影响.
- 在Pt催化剂中利用应变,特别是使用核心外结构,提高了性能,但对于特定反应的详细应变活性相关性仍然具有挑战性.
研究的目的:
- 在基于的纳米立方体上的超薄外中精确控制格子应变的方法.
- 在这些工程Pt催化剂上研究甲醇氧化和演变反应的应变活性相关性.
主要方法:
- 在基于的纳米立方体上沉积超薄的Pt外.
- 通过Pd核心的化和脱化,诱导可调节的晶格应变,将应变从-5.1%调到5.9%.
- 在不同压力条件下评估甲醇氧化和演变反应的电催化性能.
主要成果:
- 在Pt外中实现精确控制格子应变,范围为-5.1%至5.9%.
- 证明压力显著调整Pt外的电催化活性.
- 观察到不同的应变活性关系:甲醇氧化的M形曲线和进化的火山形曲线.
结论:
- 开发的应变工程方法可为特定反应微调 Pt 催化剂性能.
- 这种方法提供了一种选和优化晶格应变的途径,以提高Pt和潜在的其他金属催化剂的性能.
- 了解这些应变活性相关性对于设计下一代能量转换电催化剂至关重要.
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