关于电催化在非水性Li-O2电池中的有效性
Bryan D McCloskey1, Rouven Scheffler, Angela Speidel
1IBM Almaden Research Center, San Jose, California 95120, United States. bmcclos@us.ibm.com
Journal of the American Chemical Society
|October 15, 2011
概括
研究人员发现,氧电池中的传统阴极电催化主要催化了电解质分解,而不是氧气进化. 这表明,在这些系统中,用于氧气进化的传统电催化可能是不必要的.
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
- 储能 储能 储能 储能 储能 储能
背景情况:
- 可充电空气 (Li-O2) 电池正在研究其高能量密度.
- 减少氧减少和演化反应中的过量潜力对于氧电池效率至关重要.
- 不同质的电催化是提高Li-O2电池性能的一个关键重点.
研究的目的:
- 研究非水性Li-O2电池中传统阴极材料的真正催化活性.
- 为了区分氧气进化和电解质分解催化.
- 评估传统氧气演化电催化剂的必要性.
主要方法:
- 使用Au,Pt和MnO2纳米粒子作为阴极催化剂对Li-O2细胞进行电化学测试.
- 在二甲氧乙 (DME) 电解液中的反应产物的分析.
- 催化活性与纯碳电极的比较.
主要成果:
- 过去关于Li-O2电池中阴极电催化反应的报道得到证实,但归因于电解质溶剂分解.
- 在DME中没有观察到Au,Pt和MnO2纳米颗粒对氧气进化的显著催化活性.
- 过氧化物 (Li2O2) 形成是DME中占主导地位的电化学产品.
- 氧的进化开始潜力仅略高于开放电路潜力.
结论:
- 传统的阴极电催化剂主要催化电解质分解,而不是在非水性Li-O2电池中所需的氧气演变.
- 在以前的研究中观察到的催化效应可能是由于副作用,而不是真正的氧气进化催化.
- 传统的氧化演化电催化可能是不必要的,以改善Li-O2电池的性能,鉴于其较低的发作潜力.
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