一氧化碳的优先氧化,由纳米颗粒催化在半孔中
Atsushi Fukuoka1, Jun-ichi Kimura, Tadashi Oshio
1Catalysis Research Center, Hokkaido University, N-21 W-10, Sapporo 001-0021, Japan. fukuoka@cat.hokudai.ac.jp
Journal of the American Chemical Society
|August 1, 2007
概括
在半孔中纳米颗粒显示出对二氧化碳的优先氧化 (PROX) 的卓越性能,这对于在低温下净化燃料电池的燃料至关重要.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
背景情况:
- 对一氧化碳 (CO) 的优先氧化 (PROX) 对于净化聚合物电解质燃料电池的 (H2) 是至关重要的.
- 现有的贵金属催化剂在低工作温度下表现不佳,难以应对.
研究的目的:
- 开发高活性,选择性和耐用的催化剂,用于H2净化中的低温CO氧化.
- 在PROX反应中阐明中孔性二氧化支的纳米颗粒的催化机制.
主要方法:
- 在中孔上支持纳米颗粒的合成.
- 在353K以下的PROX反应中对催化性能的评估.
- 现场红外光谱学使用同位素追踪技术来研究反应机制.
主要成果:
- 半孔中的Pt纳米粒子在353K以下的PROX中表现出前所未有的活性,选择性和耐久性.
- 反应机制涉及将氧气从半孔性二氧化融入CO2中,而不是直接使用气相O2.
- 在半孔上表面的基 (OH) 群促进Pt上的CO氧化,而不会形成水.
结论:
- 半孔二氧化显著增强了Pt纳米颗粒的催化性能,用于低温PROX.
- 涉及氧和表面OH组的独特机制为高效的CO氧化提供了一条新的途径.
- 这种催化剂系统有望推动燃料电池的净化技术的发展.
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