在低温CO2化中驱动甲醇形成的TiO2支持的Re的双功能性
Nat Phongprueksathat1, Kah Wei Ting2, Shinya Mine2
1Catalysis Engineering, Department of Chemical Engineering, Delft University of Technology, Van der Maasweg 9, Delft 2629 HZ, Netherlands.
ACS catalysis
|August 24, 2023
概括
在二氧化 (Re/TiO2) 催化剂上具有高度活性的,可在低温下促进二氧化碳化成甲醇. 这项研究揭示了Re/TiO22.
科学领域:
- 催化剂是一种催化剂.
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 将二氧化碳化成甲醇对于可持续能源至关重要.
- 低温 (<200°C) 催化在热力学上有利,但在动力学上具有挑战性.
- 像Cu/ZnO/Al2O3这样的现有催化剂在低温下表现出局限性.
研究的目的:
- 为了阐明二氧化碳化Re/TiO2催化剂中的活性位点和活性物种.
- 了解低温中甲醇形成的机制.
- 为了比较Re/TiO2与工业催化剂的性能.
主要方法:
- 在现场/操作的X射线吸收光谱学.
- 拉曼光谱法 拉曼光谱法 拉曼光谱法
- 环境压力X射线光电子光谱学 (AP-XPS)
- 分散反射率红外里埃变换光谱学 (DRIFTS)
主要成果:
- 在125-200°C和高压下,Re/TiO2比Cu/ZnO/Al2O3具有更高的活性和甲醇选择性.
- 二氧化碳的激活形成了在阴离子Re物种上的活性形式中间体.
- 金属Re集群促进H2激活并形成化.
- 电离子Re单个原子和金属Re集群共存,推动甲醇的形成.
结论:
- 电离子Re单个原子和金属Re团的协同效应是Re/TiO2在低温高活性的关键.
- 了解活性中间体对于设计高效的二氧化碳转化催化剂至关重要.
- Re/TiO2为低温二氧化碳转化为甲醇提供了一个有希望的替代方案.
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