为高效的氧气还原反应和氧气演化反应提供基于酸的铁/分子催化剂: 构建带有基的内置电场
Jingshun Shen1, Qi Liu1, Yuexing Zhang2
1School of Materials Science and Engineering, China University of Petroleum (East China), Qingdao 266580, PR China.
Journal of colloid and interface science
|November 12, 2023
概括
一种新的双功能催化剂Fe[Pc(I) ]+Ni[Pc(I) ]@NCPDI,可以增强可充电Zn-空气电池. 这种催化剂表现出优异的氧降解和进化反应,性能优于金和氧化物基准.
科学领域:
- 电化学和材料科学 材料科学
- 专注于开发用于储能应用的先进催化剂.
背景情况:
- 可充电的Zn-空气电池需要高效的电催化剂来减少氧气 (ORR) 和氧气演变 (OER).
- 现有的催化剂往往缺乏双功能性或实际应用的足够耐用性.
研究的目的:
- 为ORR和OER设计和合成一种新的双功能分子催化剂.
- 研究可充电Zn-空气电池的催化机制和性能.
- 通过合理的分子设计,增强催化剂活性和耐用性.
主要方法:
- 通过π-π相互作用,四多甲氨酸 (Fe[Pc(I) 4和Ni[Pc(I) 4) 自组装到N-化碳 (NCPDI) 上.
- 催化剂结构和电子性质的表征.
- 在性介质中进行ORR和OER的电化学测试,包括Zn-空气电池性能评估.
- 密度函数理论 (DFT) 计算以阐明催化机制.
主要成果:
- Fe[Pc(I) [4]+Ni[Pc(I) ]@NCPDI催化剂表现出高ORR半波潜力 (0.940V) 和低OER超电位 (298mV在10mA cm-2).
- 性能超过了商业Pt/C和RuO2催化剂,以及单元催化剂.
- DFT的计算证实了ORR速率决定阶段的能量障碍降低,这归因于诱导的电子效应.
- 催化剂在可充电Zn-空气电池中表现出极好的耐用性.
结论:
- 开发的双功能催化剂在可充电Zn-空气电池中显示出ORR和OER的特殊活性和稳定性.
- 在基上加入基的策略有效调节电子性质并提高催化性能.
- 这项工作为设计高性能多功能分子电催化剂提供了一种简单而有效的方法.
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