In situ visualizing reveals potential drive of lattice expansion on defective support toward efficient removal of nitrogen oxides.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 38830101.
- Also identified by DOI 10.1073/pnas.2311180121 and PMC identifier 11181023.
- Licence recorded as CC BY-NC-ND.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
As a sustainable and promising approach of removing of nitrogen oxides (NO<sub>x</sub>), catalytic reduction of NO<sub>x</sub> with H<sub>2</sub> 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 WO<sub>3-x</sub> support in Pt-WO<sub>3-x</sub> catalyst induced by NO in the exemplified reduction of NO with H<sub>2</sub> 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 WO<sub>3-x</sub> and favorably induce the reversible stretching of W-O-W bonds during the reaction, which can reduce the adsorption energy of NO on Pt<sub>4</sub> centers and the energy barrier of the rate-determining step. The comprehensive studies reveal that lattice expansion of WO<sub>3-x</sub> support can tune the catalytic performance of Pt-WO<sub>3-x</sub> catalyst, leading to 20% catalytic activity enhancement for the exemplified reduction of NO with H<sub>2</sub>. This work reveals that the lattice expansion of defective support can tune and optimize the catalytic performance at the atomic scale.