在氧化物中调整氧气空隙,依据配置
Mengyuan Zhang1, Xiaolan Duan1, Ying Gao2
1School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China.
ACS applied materials & interfaces
|September 23, 2023
概括
高性五氧化物 (HEO) 中的工程配置显著增加氧空缺,增强CO/C3H6氧化的催化活性. 这种方法超越了氧化物催化剂的传统兴奋剂限制.
科学领域:
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
- 表面化学 表面化学
背景情况:
- 调整表面氧气空缺对于优化氧化物催化剂性能至关重要.
- 创建氧气空缺的传统兴奋剂方法受到兴奋剂耐受性 (通常<10%) 的限制.
研究的目的:
- 提出和验证一种新的工程配置的原理,以调整氧化物催化剂中的氧气空缺.
- 为了研究配置和氧空位形成能量之间的关系.
- 为了证明由于增加氧气空缺而导致高氧氧的催化活性增强.
主要方法:
- 密度函数理论 (DFT) 计算以估计氧空位形成能量.
- 合成单双氧化物和高率二元氧化物 (HEO).
- 使用O1s XPS,O2-TPD,EPR,H2-TPR,in situ XPS和in situ XRD进行表征.
- 在CO/C3H6氧化中催化性能的评估.
主要成果:
- 在配置和氧空位形成能量之间发现了正相关性.
- 与单一或二元氧化物相比,高温氧化物表现出明显更高的氧气空置度.
- 高温电机显示过渡金属离子的降解温度较低,这是由于氧空位形成能量较低.
- 高性 (MnCuCo3NiFe) O催化剂在CO/C3H6氧化中表现出优越的催化活性.
结论:
- 工程配置是一种有效的策略,用于增加氧化物催化剂中的氧气空缺.
- 高氧化物为开发具有增强性能的先进催化剂提供了一个有希望的途径.
- 这项工作为设计具有量身定制的氧空位度的氧化物催化剂提供了新的视角.
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