Defective TiOx overlayers catalyze propane dehydrogenation promoted by base metals

• 成果类型: Article
• 署名作者: Chen, Sai; Xu, Yiyi; Chang, Xin; Pan, Yue; Sun, Guodong; Wang, Xianhui; Fu, Donglong; Pei, Chunlei; Zhao, Zhi-Jian; Su, Dong; Gong, Jinlong
• 署名单位: Tianjin University; Collaborative Innovation Center of Chemical Science & Engineering Tianjin; Tianjin University; TJU-NUS Joint Institute; Chinese Academy of Sciences; Institute of Physics, CAS; Nankai University; Haihe Laboratory of Sustainable Chemical Transformations; Tianjin University
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-13061
• DOI: 10.1126/science.adp7379
• 发表日期: 2024-07-19
• 页码: 295-300
• 关键词: finding saddle-points; oxidative dehydrogenation; propylene hydrogenation; support interactions; raman-spectroscopy; platinum catalyst; modified zsm-5; plus u; oxide; performance

摘要

The industrial catalysts utilized for propane dehydrogenation (PDH) to propylene, an important alternative to petroleum-based cracking processes, either use expensive metals or metal oxides that are environmentally unbenign. We report that a typically less-active oxide, titanium oxide (TiO2), can be combined with earth-abundant metallic nickel (Ni) to form an unconventional Ni@TiOx catalyst for efficient PDH. The catalyst demonstrates a 94% propylene selectivity at 40% propane conversion and superior stability under industrially relevant conditions. Complete encapsulation of Ni nanoparticles was allowed at elevated temperatures (>550 degrees C). A mechanistic study suggested that the defective TiOx overlayer consisting of tetracoordinated Ti sites with oxygen vacancies is catalytically active. Subsurface metallic Ni acts as an electronic promoter to accelerate carbon-hydrogen bond activation and hydrogen (H-2) desorption on the TiOx overlayer.