在分层的双氧化物中,间隙诱导的不可逆转的晶格扭曲
Deok Ki Cho1, Hyun Woo Lim1, Andi Haryanto2
1Department of Materials Science and Engineering, Seoul National University, Seoul 08826, Republic of Korea.
ACS nano
|July 22, 2024
概括
在铁层双氧化物 (NiFe LDHs) 中引入格子应变增强了氧演化反应 (OER) 电催化剂活性. 一种硫酸离子间歇方法诱导不可逆转的格子扭曲,稳定活性相并提高性能.
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:
- 格子应变是通过调整电子结构和中间约束能来增强电催化剂活性的一个关键因素.
- 铁层双氧化物 (NiFe LDHs) 是氧化演化反应 (OER) 的有效电催化剂.
- 扭曲的β-NiOOH和未扭曲的γ-NiOOH相之间的可逆转换限制了NiFe LDHs的长期OER活性.
研究的目的:
- 开发一种方法来诱导NiFe LDHs的不可逆转的格子扭曲,以增强OER活动和稳定性.
- 调查格子扭曲影响OER期间NiFeLDH电子结构和相位稳定的机制.
- 展示格子应变工程的潜力,作为提高电催化剂性能的总体策略.
主要方法:
- tungstate (BWO) 离子间接到NiFe LDHs中.
- 氧化演化反应 (OER) 活动的电化学表征,包括超电位和Tafel斜率测量.
- 在现场的拉曼光谱法用于监测OER条件下的相变.
主要成果:
- tungstate 离子间歇方法成功诱导了NiFe LDHs (D-NiFe LDHs) 的不可逆转的晶格扭曲.
- D-NiFe LDHs表现出显著增强的OER活性,具有较低的超电位 (209 mV在10 mA cm-2和276 mV在500 mA cm-2) 和33.4 mV dec-1的Tafel斜率.
- 在现场的拉曼光谱学证实了D-NiFe LDHs在OER条件下活性β-NiOOH相的稳定,并且该材料在500 mA cm-2下50小时表现出色的稳定性.
结论:
- 由BWO离子间隙引起的不可逆转的晶格扭曲有效地增强了NiFe LDHs的OER活性和稳定性.
- 间隔诱导格子应变的策略为设计高性能电催化剂提供了一种一般方法.
- 通过格子应变稳定扭曲的β-NiOOH阶段对于实现优越和持久的OER性能至关重要.
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