使用金集群稳定氧减氧电催化剂
1Department of Chemistry, Brookhaven National Laboratory, Upton, NY 11973, USA.
Science (New York, N.Y.)
|January 16, 2007
概括
黄金集群稳定了燃料电池催化剂的降解. 用黄金修改纳米颗粒可以防止在潜在循环过程中溶解,从而保持用于车辆应用的催化剂性能.
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:
- 燃料电池对于清洁能源至关重要,但催化剂随着时间的推移而降解.
- 纳米颗粒的溶解是燃料电池耐用性的一个主要挑战,特别是在动态运行条件下的车辆.
研究的目的:
- 为了提高 (Pt) 氧降解反应 (ORR) 电催化剂的稳定性.
- 为了减轻在潜在循环过程中Pt纳米颗粒的溶解,这是汽车燃料电池应用中的一个常见问题.
主要方法:
- 用金 (Au) 集群对纳米粒子进行修改.
- 在ORR条件下,电化学测试涉及在0.6和1.1伏之间进行超过30,000个周期的潜在循环.
- 在现场的X射线吸收近边谱 (XANES) 和循环电压测量 (CV).
主要成果:
- 与纯Pt相比,Au-修改的Pt电催化剂表现出明显增强的抗溶性稳定性.
- 在经过大量循环后,观察到Au-修饰的Pt活性和表面积的微不足道变化.
- 在相同的条件下,纯Pt催化剂在活性和表面积方面表现出相当大的损失.
结论:
- 黄金集群有效地稳定燃料电池电催化剂,防止溶解.
- 增强的稳定性归因于黄金集群提高了的氧化潜力.
- 这种稳定策略为改善车辆燃料电池中催化剂的耐用性提供了一个有希望的解决方案.
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