{"title":"Single atom doping induced charge-specific distribution of Cu1-TiO2 for selective aniline oxidation via a new mechanism","authors":"","doi":"10.1016/S1872-2067(24)60104-X","DOIUrl":null,"url":null,"abstract":"<div><p>Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites, achieving precise selectivity control in complex organic reactions, is a highly desirable yet challenging endeavor. Meanwhile, identifying the active site also represents a significant obstacle, primarily due to the intricate electronic environment of single atom site doped metal oxide. Herein, a single atom Cu doped TiO<sub>2</sub> catalyst (Cu<sub>1</sub>-TiO<sub>2</sub>) is prepared <em>via</em> a simple “colloid-acid treatment” strategy, which switches aniline oxidation selectivity of TiO<sub>2</sub> from azoxybenzene to nitrosobenzene, without using additives or changing solvent, while other metal or nonmetal doped TiO<sub>2</sub> did not possess. Comprehensive mechanistic investigations and DFT calculations unveil that Ti-O active site is responsible for triggering the aniline to form a new PhNOH intermediate, two PhNOH condense to azoxybenzene over TiO<sub>2</sub> catalyst. As for Cu<sub>1</sub>-TiO<sub>2</sub>, the charge-specific distribution between the isolated Cu and TiO<sub>2</sub> generates unique Cu<sub>1</sub>-O-Ti hybridization structure with nine catalytic active sites, eight of them make PhNOH take place spontaneous dissociation to produce nitrosobenzene. This work not only unveils a new mechanistic pathway featuring the PhNOH intermediate in aniline oxidation for the first time but also presents a novel approach for constructing single-atom doped metal oxides and exploring their intricate active sites.</p></div>","PeriodicalId":9832,"journal":{"name":"Chinese Journal of Catalysis","volume":null,"pages":null},"PeriodicalIF":15.7000,"publicationDate":"2024-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Chinese Journal of Catalysis","FirstCategoryId":"92","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S187220672460104X","RegionNum":1,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CHEMISTRY, APPLIED","Score":null,"Total":0}
引用次数: 0
Abstract
Utilizing single atom sites doping into metal oxides to modulate their intrinsic active sites, achieving precise selectivity control in complex organic reactions, is a highly desirable yet challenging endeavor. Meanwhile, identifying the active site also represents a significant obstacle, primarily due to the intricate electronic environment of single atom site doped metal oxide. Herein, a single atom Cu doped TiO2 catalyst (Cu1-TiO2) is prepared via a simple “colloid-acid treatment” strategy, which switches aniline oxidation selectivity of TiO2 from azoxybenzene to nitrosobenzene, without using additives or changing solvent, while other metal or nonmetal doped TiO2 did not possess. Comprehensive mechanistic investigations and DFT calculations unveil that Ti-O active site is responsible for triggering the aniline to form a new PhNOH intermediate, two PhNOH condense to azoxybenzene over TiO2 catalyst. As for Cu1-TiO2, the charge-specific distribution between the isolated Cu and TiO2 generates unique Cu1-O-Ti hybridization structure with nine catalytic active sites, eight of them make PhNOH take place spontaneous dissociation to produce nitrosobenzene. This work not only unveils a new mechanistic pathway featuring the PhNOH intermediate in aniline oxidation for the first time but also presents a novel approach for constructing single-atom doped metal oxides and exploring their intricate active sites.
期刊介绍:
The journal covers a broad scope, encompassing new trends in catalysis for applications in energy production, environmental protection, and the preparation of materials, petroleum chemicals, and fine chemicals. It explores the scientific foundation for preparing and activating catalysts of commercial interest, emphasizing representative models.The focus includes spectroscopic methods for structural characterization, especially in situ techniques, as well as new theoretical methods with practical impact in catalysis and catalytic reactions.The journal delves into the relationship between homogeneous and heterogeneous catalysis and includes theoretical studies on the structure and reactivity of catalysts.Additionally, contributions on photocatalysis, biocatalysis, surface science, and catalysis-related chemical kinetics are welcomed.