In situ visualizing reveals potential drive of lattice expansion on defective support toward efficient removal of nitrogen oxides

• 成果类型: Article
• 署名作者: Hao, Zhifei; Liu, Guoquan; Wang, Pengfei; Zhang, Weiyu; Sun, Wenming; Zheng, Lirong; Guo, Shaojun; Zhan, Sihui
• 署名单位: Nankai University; Peking University; Capital Normal University; Chinese Academy of Sciences; Institute of High Energy Physics, CAS
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-15159
• DOI: 10.1073/pnas.2311180121
• 发表日期: 2024-06-11
• 关键词: atomic-scale view; active-sites; co oxidation; single-atom; hydrogen; nanoparticles; temperature; reduction; molecules; catalysis

摘要

As a sustainable and promising approach of removing of nitrogen oxides (NOx), catalytic reduction of NOx with H-2 is highly desirable with a precise understanding to the structure-activity relationship of supported catalysts. In particular, the dynamic evolution of support at microscopic scale may play a critical role in heterogeneous catalysis, however, identifying the in situ structural change of support under working condition with atomic precision and revealing its role in catalysis is still a grand challenge. Herein, we visually capture the surface lattice expansion of WO3-x support in Pt-WO3-x catalyst induced by NO in the exemplified reduction of NO with H-2 using in situ transmission electron microscopy and first reveal its important role in enhancing catalysis. We find that NO can adsorb on the oxygen vacancy sites of WO3-x and favorably induce the reversible stretching of W-O-W bonds during the reaction, which can reduce the adsorption energy of NO on Pt-4 centers and the energy barrier of the rate-determining step. The comprehensive studies reveal that lattice expansion of WO3-x support can tune the catalytic performance of Pt-WO3-x catalyst, leading to 20% catalytic activity enhancement for the exemplified reduction of NO with H-2. This work reveals that the lattice expansion of defective support can tune and optimize the catalytic performance at the atomic scale.