切换电气双层潜力按阶段结构控制,用于先进的氧降低反应的@化碳核心外
Seonghee Kim1, Seulgi Ji2, Soyoon Jeong1
1School of Materials Science and Engineering, Pusan National University, 2 Busandaehak-ro 63beon-gil, Geumjeong-gu, Busan, 46241, Republic of Korea.
Small (Weinheim an der Bergstrasse, Germany)
|December 27, 2023
概括
设计先进的氧降解反应 (ORR) 电催化剂需要平衡氧中间体吸附和脱附. 六角密封包装 (HCP) /N-化碳 (Cobalt@NC) 催化剂与面中心立方 (FCC) 结构相比,显示出更高的ORR活性.
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:
- 设计高效的氧降解反应 (ORR) 电催化剂对于能量转化技术至关重要.
- 一个关键的挑战在于优化催化剂表面上氧气中间体的吸附和脱附.
- /N-碳 (Cobalt@NC) 核心外结构是有前途的ORR电催化剂.
研究的目的:
- 系统地评估和比较六角密封 (HCP) 和面中心立方 (FCC) 芯外Cobalt@NC催化剂的ORR活性.
- 用理论和实验方法阐明影响ORR性能的基础电子结构效应.
主要方法:
- 密度函数理论 (DFT) 计算来研究电子结构和界面极化.
- 对HCP和FCCCobalt@NC催化剂的实验合成和表征.
- 在空气电池中对ORR活动和性能进行电化学评估.
主要成果:
- 与FCC Cobalt@NC.NC相比,DFT的计算表明,HCP Cobalt@NC可以更容易地使氧气中间体脱氧,而不是FCC Cobalt@NC.NC.
- 经过等离子工程的HCP Cobalt@NC表现出显著增强的ORR动力学,其动力电流密度为6.24 mA cm-2在0.85 V与RHE的0.85 V下.
- 在ORR活动和空气电池性能方面,HCP Cobalt@NC的表现优于FCC Cobalt@NC和商业20%的Pt/C.
结论:
- 该研究表明,芯的晶体结构 (HCP与FCC) 极大地影响了Cobalt@NC催化剂的ORR性能.
- HCP Cobalt@NC表现出优越的催化活性和ORR的耐用性,归因于优化的氧中间体脱吸.
- 这些发现凸显了HCP Cobalt@NC作为ORR应用中基催化剂的非常有前途,具有成本效益的替代品.
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