空间限制的Pt合金加快了燃料电池氧气减少的质量运输
Yuxin Gao1, Hang Liu1, Xintian Wang2,3
1State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, P. R. China.
Small (Weinheim an der Bergstrasse, Germany)
|September 9, 2024
概括
研究人员开发了一种新的-锡 (PtSn) 合金催化剂,用于质子交换膜燃料电池. 这种催化剂通过降低质量传输阻力来提供高活性和耐用性,这对于高效的能量转换至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 纳米技术 纳米技术
背景情况:
- 质子交换膜燃料电池 (PEMFC) 需要高效的基 (Pt) 合金催化剂来实现高性能.
- 催化剂中低Pt负载导致诸如高质量运输阻力等挑战,阻碍燃料电池效率.
- 开发具有增强活性和耐久性的催化剂仍然是燃料电池技术的重大障碍.
研究的目的:
- 开发一种先进的PtSn合金催化剂,提高PEMFCs的质量活性和耐用性.
- 为了应对高质量运输阻力与低Pt负载相关的挑战.
- 研究受控合金和纳米结构对催化剂性能的影响.
主要方法:
- 利用原子层沉积 (ALD) 精确地将金属前体引入介质纳米颗粒 (NP) 在半孔通道内.
- 控制的沉积地点和数量,以实现空间有限的合金.
- 描述了PtSn合金催化剂在膜电极组件 (MEA) 中的尺寸,分布和电化学性能.
主要成果:
- 准备的PtSn合金催化剂具有小 (2.10 ± 0.53 nm) 和均的粒子大小在mesopores.
- 在0.9V时达到0.85A/mg的高初始质量活性,这归因于报告中最低的局部氧气传输电阻 (3.68S m-1).
- 经过3万个循环后,证明了卓越的全细胞耐用性,质量活动仅下降了11%.
结论:
- 开发的 PtSn 合金催化剂由于减少氧中间吸附能量和强大的 Pt-Sn 电子相互作用而表现出增强的活性和耐用性.
- 基于ALD的空间限制合金是一种有效的策略,用于创建高性能燃料电池催化剂.
- 催化剂显示出对推进质子交换膜燃料电池技术的重大前景.
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