在Pd/TiO2上进行逆水气转移反应的活性场合合集:两个比一个或多个更好
1College of Chemistry, Nankai University, Tianjin 300071, China.
ACS applied materials & interfaces
|February 11, 2025
概括
在TiO2上的团上进行逆水气转移 (rWGS) 反应的最佳活性组合是双原子位点 (Pd2). 这个Pd2集群与单个原子或更大的集群相比,表现出更高的催化活性,为催化剂设计提供了洞察力.
科学领域:
- 催化科学是一种催化科学.
- 材料科学是一种材料科学.
- 表面化学 表面化学
背景情况:
- 确定催化反应的活性部位大小至关重要,但具有挑战性.
- 反向水气转移 (rWGS) 反应对于二氧化碳利用非常重要.
研究的目的:
- 系统地调查rWGS反应的最佳活性组合数.
- 为了探索在 anatase TiO2 (A-TiO2) 上支持的集群 (Pd_n) 的催化性能,n = 1, 2, 3, 4.
主要方法:
- 密度函数理论 (DFT) 的计算.
- 中场微动力学建模.
- 对反应能量图和中间结合能量的分析.
主要成果:
- 二聚合物 (Pd2) 显示出对rWGS反应的最高催化活性.
- 单个 Pd 原子 (Pd1) 显示出有限的活性,原因是碳酸形成的活性位点不足.
- 较大的群 (Pd3,Pd4) 由于过度强烈的H*结合而表现出较低的活性,阻碍了碳酸的形成.
- Pd2为关键中间体 ([COOH* + H*]) 提供了最稳定的配置.
结论:
- 活跃组合大小显著影响rWGS的催化活性.
- 结合能量作为rWGS活动的描述符,与萨巴蒂耶原理保持一致.
- 对于rWGS催化和潜在的其他反应,如水气转移 (WGS),Pd2集群是有前途的.
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