Suzuki Kenta, Hasegawa Shingo, Osuga Ryota, Nakajima Kiyotaka, Motokura Ken
Department of Chemistry and Life Science, Yokohama National University, Yokohama, 240-8501, Japan.
Institute for Catalysis, Hokkaido University, Sapporo, 001-0021, Japan.
Small. 2025 Feb;21(8):e2408226. doi: 10.1002/smll.202408226. Epub 2025 Jan 23.
Hydrogen spillover, particularly when involving "interparticle" hydrogen spillover, offers a unique opportunity to enhance catalytic efficiency by remote activation of surface acidity. Building on this concept, this study aims to investigate physically mixed alumina-supported platinum nanoparticles (Pt/AlO) and zirconia-supported tungsten oxide (WO/ZrO) in promoting the direct synthesis of cumene from benzene and propane at 300 °C. The reaction with Pt/AlO alone afforded propylene as the only product, indicating the successive reaction route of Pt-catalyzed dehydrogenation of propane, followed by acid-catalyzed alkylation. WO/ZrO with 18 wt.% WO loading resulted in high benzene conversion (≈5.0%) and cumene selectivity (≈87.5%), which possesses poly tungstate species on the surface that is active for the acid-catalyzed alkylation. UV-vis-near infrared spectroscopy, X-ray photoelectron spectroscopy, and in situ Fourier-transform infrared spectroscopy analyses revealed that atomic hydrogen abstracted from propane spills over from Pt/AlO particles to WO/ZrO particles to form Brønsted acid sites on the poly tungstate species, whose activity for alkylation between benzene and propylene is double that of the parent WO/ZrO.
氢溢流,特别是涉及“颗粒间”氢溢流时,为通过远程激活表面酸度来提高催化效率提供了独特的机会。基于这一概念,本研究旨在研究物理混合的氧化铝负载铂纳米颗粒(Pt/AlO)和氧化锆负载氧化钨(WO/ZrO)在300℃下促进由苯和丙烷直接合成异丙苯的情况。单独使用Pt/AlO进行反应时,仅得到丙烯作为唯一产物,这表明丙烷经Pt催化脱氢,随后进行酸催化烷基化的连续反应路线。负载量为18 wt.% WO的WO/ZrO具有较高的苯转化率(约5.0%)和异丙苯选择性(约87.5%),其表面具有对酸催化烷基化有活性的聚钨酸盐物种。紫外可见近红外光谱、X射线光电子能谱和原位傅里叶变换红外光谱分析表明,从丙烷中提取的原子氢从Pt/AlO颗粒溢流到WO/ZrO颗粒上,在聚钨酸盐物种上形成布朗斯特酸位点,其对苯与丙烯之间烷基化的活性是母体WO/ZrO的两倍。