用于减少氧气的L10三级纳米颗粒的异型应变调整
Junrui Li1, Shubham Sharma2, Kecheng Wei1
1Department of Chemistry, Brown University, Providence, Rhode Island 02912, United States.
Journal of the American Chemical Society
|October 30, 2020
概括
控制纳米粒子表面应变可以增强能量反应的催化作用. 一个自力模型和实验表明L10-CoNiPt纳米粒子显著提高了氧降解反应活性和稳定性.
科学领域:
- 材料科学
- 催化剂
- 表面科学
背景情况:
- 纳米粒子 (NP) 催化剂的性能对于能量转化反应至关重要.
- 控制NP表面应变是优化NP催化的一个关键策略.
- 氧降解反应 (ORR) 是许多能源技术中的一个重要过程.
研究的目的:
- 对氧降解反应 (ORR) 的应变诱导催化增强进行研究.
- 用自力模型预测纳米粒子表面的异性压力水平.
- 通过实验验证L10-CoMPt (M = Mn,Fe,Ni,Cu,Ni) 纳米粒子催化剂的预测应变效应.
主要方法:
- 开发和应用自力模型来预测Pt{111) 表面的二维应变.
- 合成5nmL10-CoMPt合金纳米粒子.
- 对ORR催化活性和合成NP的稳定性进行实验评估.
- 实验结果与2D理论火山图的比较.
主要成果:
- 自力模型成功预测了异型应变水平.
- 合成的L10-CoMPtNP表现出增强的ORR催化活性,符合理论预测.
- L10-CoNiPtNP表现出卓越的性能,其质量活性为3. 1A/ mgPt,特异性活性为9. 3mA/ cm2.
- 性能最好的L10-CoNiPt催化剂表现出极好的稳定性,在30,000个循环后仅有15.9%的质量活性损失.
结论:
- 表面应变工程是优化NP催化剂的有效策略.
- 自力模型为预测催化过程中的应变效应提供了有价值的工具.
- L10-CoNiPt纳米颗粒代表了氧降解反应的非常有前途的催化剂,提供了增强的活性和耐久性.
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