Boosting Oxygen Activation via Defect Engineering to Regulate CO Oxidation Pathway over Pt/TiO 2 Catalysts

作者：Yang Zou, Xue Li, Yongqi Zhao, Xiaolong Liu, Shaohua Xie, Fudong Liu, Tingyu Zhu · 发表于：ACS Catalysis · 年份：2025 · DOI：10.1021/acscatal.4c04827 · 被引用次数：30 · 研究领域：Catalytic Processes in Materials Science、Semiconductor materials and devices、Catalysis and Oxidation Reactions

Defect engineering has attracted great attention due to its important role in promoting metal dispersion and regulating catalytic performance. In this study, a gentle method for stabilizing metal single atoms and adjusting the metal coordination environment was proposed, wherein the chemical etching of a Ti–Si oxide composite by NaOH was employed to construct a defect structure. As a conceptual proof, a defective catalyst loaded with 0.1 wt % Pt was synthesized, which exhibited a complete CO oxidation temperature of 200 °C, a significant 70 °C decrease compared to the conventional catalyst. Characterization and theoretical calculations confirmed that Pt existed as single atoms on the defective catalyst, and O 2 was adsorbed and activated at Ti 3+ defect sites. Notably, the CO oxidation followed the Mars-van Krevelen (MvK) mechanism, resulting in a remarkably low oxygen activation energy barrier of 0.38 eV on the defective catalyst, significantly lower than that on the conventional catalyst (2.48 eV), consistent with its enhanced low-temperature activity. This work provides a promising strategy for the design of efficient and stable low-load noble metal catalysts on oxide-based supports.