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在空气电池的三原子催化剂中的工程对称度破坏中心和d轨道调制
Junjie Zhong1, Zhanhao Liang1, Ning Liu1
1State Key Laboratory of Optoelectronic Materials and Technologies, Guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices, Nanotechnology Research Center, School of Materials Science and Engineering, Sun Yat-sen University, Guangzhou 510275, People's Republic of China.
ACS nano
|February 5, 2024
概括
一种新型的三原子催化剂 (TAC) 证明了对氧减少和进化反应的优越双功能氧气电催化. 这一突破为空气电池提供了更高的稳定性和性能,即使在低温下也是如此.
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:
- 在三原子催化剂 (TAC) 中理解双功能氧气电催化剂的配置-活性关系是具有挑战性的.
- 现有的单原子和二原子催化剂在性能和稳定性方面存在局限性.
研究的目的:
- 开发一种具有三核活性结构的新型三原子催化剂 (TAC),用于增强氧气电催化.
- 研究TAC中的协同增强机制和配置-活动关系.
- 评估TAC在水性和准固态空气电池 (ZAB) 的表现.
主要方法:
- 三核三原子催化剂 (TAC) 的合成和表征.
- 氧降解反应 (ORR) 和氧演化反应 (OER) 的电催化试验.
- 使用基于TAC的阴极制造和测试空气电池 (ZAB).
- 实验和理论分析 (例如,d轨道调制,结合强度) 来阐明催化机制.
主要成果:
- 在ORR和OER方面,TAC显著优于单原子和二原子催化剂.
- 基于TAC的ZAB表现出异常的可充电稳定性 (1970h在2 mA cm−2) 和循环性能.
- 准固态ZAB显示出出色的低温适应性 (-60°C) 和可充电性.
- 与Fe和Cu结合的破坏对称性的CoN4配置调节了d轨道能量水平,削弱了氧介质结合.
结论:
- 异种TAC的理性三协调设计使得卓越的双功能氧气电催化.
- TAC为开发ZAB等高性能储能设备提供了一个有前途的途径.
- 该研究为先进的电催化应用提供了对TAC的深入机制性见解.
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