微弱单原子Pd催化剂用于从酸生产H2
Esmail Doustkhah1,2,3, Nao Tsunoji4, Shinya Mine5
1Research Center for Materials Nanoarchitechtonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan.
ACS applied materials & interfaces
|January 19, 2024
概括
氨基功能化二氧化上的单个原子 (PdSA) 显示出高活性,用于从酸生成H2,但它们的聚合提高了产量. 松散的Pd-N结合促进了催化,而不是基于醇的催化剂中强大的Pd-S结合.
科学领域:
- 不同质的催化剂.
- 材料科学 材料科学 材料科学
- 表面化学 表面化学
背景情况:
- 单原子催化剂 (SAC) 代表了催化剂的前沿,但它们的有效性需要对特定反应进行严格的验证.
- 酸是H2生成的有前途的载体,需要高效的催化系统.
研究的目的:
- 研究单个原子 (PdSA) 的催化性能和稳定性,这些原子支持在不同的基板上,用于从酸生成H2.
- 阐明在氨基和硫醇功能化二氧化上的PdSA催化作用的结构-活性关系.
主要方法:
- 合成PdSA催化剂在与氨基,醇和二甲基酸盐组功能化的中孔上.
- 从酸生成H2的催化活性和稳定性的评估.
- 使用密度函数理论 (DFT) 计算进行表征,以探测电子结构和结合相互作用.
主要成果:
- 在氨基功能化 (SiO2-NH2/PdSA) 上的PdSA表现出与基于硫醇的催化剂 (SiO2-S-PdSA和SiO2-NHCS2-PdSA) 相比显著更高的催化活性.
- SiO2-NH2/PdSA显示了最低的单原子稳定性,而Pd聚合矛盾地提高了反应产量.
- DFT计算显示SiO2-NH2/PdSA中松散的Pd-N结合,在费米水平附近保留了不稳定的Pd 4d电子,而在基催化剂中强的Pd-S结合降低了催化活性.
结论:
- PdSA的催化活性在很大程度上取决于支持的功能组的性质.
- 随着氨基组的观察,松结合相互作用可以增强催化活性,但损害单原子稳定性,从而导致聚合诱导的产量改善.
- 了解这些结合效应对于设计高活性和稳定的单原子催化剂至关重要.
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