在高氧化物半导体中缩小带间隙,用于增强氧化物进化催化
Rowan R Katzbaer1, Francisco Marques Dos Santos Vieira2, Ismaila Dabo2
1Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States.
Journal of the American Chemical Society
|March 15, 2023
概括
高氧化物 (HEO) 呈现带隙缩小和氧化演变的增强催化活性. 这项研究揭示了 (FeCoNiCuZn) Al2O4 的协同作用,其性能优于原始氧化物.
科学领域:
- 材料科学
- 催化剂
- 固态化学
背景情况:
- 高氧化物 (HEO) 在晶格中具有五个或更多的随机混合金属.
- 由于协同效应,这些材料可以表现出独特的增强性质,特别是在催化过程中.
- 脊柱氧化物是一种具有多样性应用的材料.
研究的目的:
- 为了研究高氧化 (Fe0.2Co0.2Ni0.2Cu0.2Zn0.2) Al2O4 (A5Al2O4) 的带隙缩小.
- 探索 A5Al2O4 的氧化演化反应 (OER) 的催化性能
- 了解观察到的电子结构起源的特性和催化行为.
主要方法:
- 高氧化氧化物A5Al2O4的合成和表征
- 分析电子带结构和状态密度的第一原理计算.
- 氧化演化反应 (OER) 活性和稳定性的电化学测试.
- 使用元素分析和放牧发生率X射线衍射 (GIXRD) 的反应后分析.
主要成果:
- A5Al2O4的带隙显著缩小,为0.9 eV,比其原始旋氧化物小.
- 第一个原则的计算将频段差距缩小归因于3D状态能量分布的扩大.
- A5Al2O4表现出优异的OER催化活性,在400mV的超电位下达到10mA/cm2.
- 在5小时后催化剂的停用与被动化表面层的形成有关.
结论:
- 在A5Al2O4中,带间隙的缩小与高成分和电子结构的修改有关.
- 高氧化物作为氧化物演变反应的有效催化剂,超过单元氧化物.
- 通过高方法设计电子结构为多元氧化物增强催化性能提供了一条途径.
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