在Ni基异构催化剂中定制溢出效应,以促进性氧化反应
Yang Yang1, Wei Zheng1, Peichen Wang1
1Hefei National Research Center for Physical Sciences at the Microscale, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei 230026, China.
这项研究引入了一种新的Ni/MoOH异构催化剂,可显著增强燃料电池中的性氧化反应 (HOR). 催化剂利用溢出效应来实现高效的中间体转移,实现与催化剂相当的性能.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 组无金属 (无PGM) 催化剂对于离子交换膜燃料电池 (AEMFC) 是必不可少的.
- 性氧化反应 (HOR) 是AEMFC的一个关键过程,但其效率受到缓慢的动力学限制.
- 现有的基于Ni的异构结构往往遭受低效的中间传输路径,阻碍HOR活动.
研究的目的:
- 设计和研究一个Ni/MoOH异构催化剂,以增强性HOR活性.
- 阐明溢出和中间转移途径在改善HOR动力学中的作用.
- 为设计先进的无PGMHOR催化剂提供见解.
主要方法:
- 合成Ni/MoOH异构催化剂.
- 在现场X射线吸收细结构 (XAFS) 和拉曼光谱.
- H/D运动同位素效应 (KIE) 测量.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 通过溢出从Ni到MoOH地点的轻松H*迁移.
- 证实了迁移的H*与OH*在接口上的反应,增强了HOR.
- 由于溢出效应,观察到金属Ni相的保存.
- 实现了高的HOR活动 (Jk,m = 58.5 mA mgNi−1,j0,s = 42 μA cmNi−2) 和功率密度 (511 mW cm−2).
结论:
- /MoOH异构结构通过通过溢出优化中间转移有效地促进HOR.
- 中间传输路径工程是设计高性能无PGMHOR催化剂的可行策略.
- 开发的催化剂对实际的AEMFC应用非常有希望.
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