联体效应诱导的电子结构操纵介质合金的介质合金,在减少氧气的5万个循环中获得了非凡的稳定性
Sijie Chen1, Dingwen Bao1, Luping Zhang1
1School of Chemistry and Chemical Engineering, Nantong University, Nantong 226019, China.
Inorganic chemistry
|November 19, 2024
概括
新的PdRhNi合金网络为离子交换膜燃料电池 (AEMFC) 提供了增强的耐用性和活性. 这一进步解决了非贵金属溶解的问题,提高了氧降解反应 (ORR) 的效率,并为商业化铺平了道路.
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
- 催化剂是一种催化剂.
背景情况:
- 商业化离子交换膜燃料电池 (AEMFC) 需要提高电催化剂的活性和耐用性.
- 在基于Pd的合金中溶解非贵金属元素仍然是一个重大挑战.
- 优化催化活性和长期稳定性之间的平衡对于AEMFC的进步至关重要.
研究的目的:
- 开发基于Pd的新型合金电催化剂,克服活动耐久性权衡.
- 为了提高氧降解反应 (ORR) 的效率和AEMFC中的CO耐受性.
- 调查联结体效应在稳定基于Pd的合金中的作用.
主要方法:
- 合成PdRhNi三元中等合金 (MEA) 网络 (PdRhNi ANs).
- 理论计算以了解电子结构和催化机制.
- 电化学测试ORR活性,耐CO中毒性和长期稳定性.
- 使用开发的电催化剂制造和测试AEMFC.
主要成果:
- PdRhNi ANs表现出优越的ORR电催化特性,其半波电位为0.85V.
- 催化剂表现出对二氧化碳毒性的优异耐受性和在5万个循环中显著的稳定性.
- 理论分析证实,Ni的联体效应优化了电子配置和吸附能.
- 使用 PdRhNi AN 阴极的 AEMFC 实现了 109 mW cm-2 的峰值功率密度.
结论:
- PdRhNi ANs代表了AEMFC的高效ORR电催化剂,克服了现有材料的关键局限性.
- 在三元合金中的联体工程是提高催化剂性能和耐久性的有希望的策略.
- 开发的MEA材料显示了AEMFC技术商业化的巨大潜力.
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