Liu Xinyu, Gu Qingqing, Zhang Yafeng, Xu Xiaoyan, Wang Hengwei, Sun Zhihu, Cao Lina, Sun Qimeng, Xu Lulu, Wang Leilei, Li Shang, Wei Shiqiang, Yang Bing, Lu Junling
Department of Chemical Physics, Hefei National Research Center for Physical Sciences at the Microscale, iChem, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, University of Science and Technology of China, Hefei 230026, Anhui, China.
CAS Key Laboratory of Science and Technology on Applied Catalysis, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
J Am Chem Soc. 2023 Mar 29;145(12):6702-6709. doi: 10.1021/jacs.2c12046. Epub 2023 Mar 15.
Reactive metal-support interactions (RMSIs) induce the formation of bimetallic alloys and offer an effective way to tune the electronic and geometric properties of metal sites for advanced catalysis. However, RMSIs often require high-temperature reductions (>500 °C), which significantly limits the tuning of bimetallic compositional varieties. Here, we report that an atomically thick GaO coating of Pd nanoparticles enables the initiation of RMSIs at a much lower temperature of ∼250 °C. State-of-the-art microscopic and spectroscopic studies disclose that low-temperature RMSIs initiate the formation of rarely reported Ga-rich PdGa alloy phases, distinct from the PdGa phase formed in traditional Pd/GaO catalysts after high-temperature reduction. In the CO hydrogenation reaction, the Ga-rich alloy phases impressively boost the formation of methanol and dimethyl ether ∼5 times higher than that of Pd/GaO. infrared spectroscopy reveals that the Ga-rich phases greatly favor formate formation as well as its subsequent hydrogenation, thus leading to high productivity.
反应性金属-载体相互作用（RMSIs）诱导双金属合金的形成，并为调整金属位点的电子和几何性质以实现先进催化提供了一种有效方法。然而，RMSIs通常需要高温还原（>500°C），这显著限制了双金属组成种类的调整。在此，我们报道，Pd纳米颗粒的原子级厚度的GaO涂层能够在约250°C的更低温度下引发RMSIs。先进的显微镜和光谱研究表明，低温RMSIs引发了罕见报道的富Ga的PdGa合金相的形成，这与传统Pd/GaO催化剂在高温还原后形成的PdGa相不同。在CO加氢反应中，富Ga合金相显著促进了甲醇和二甲醚的形成，比Pd/GaO高出约5倍。红外光谱表明，富Ga相极大地有利于甲酸盐的形成及其随后的氢化，从而导致高生产率。
