In situ formation of cocatalytic sites boosts single-atom catalysts for nitrogen oxide reduction.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 36787366.
- Also identified by DOI 10.1073/pnas.2216584120 and PMC identifier 9974487.
- 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
Nitrogen oxide (NO<sub>x</sub>) pollution presents a severe threat to the environment and human health. Catalytic reduction of NO<sub>x</sub> with H<sub>2</sub> using single-atom catalysts poses considerable potential in the remediation of air pollution; however, the unfavorable process of H<sub>2</sub> dissociation limits its practical application. Herein, we report that the in situ formation of Pt<sub>Ti</sub> cocatalytic sites (which are stabilized by Pt-Ti bonds) over Pt<sub>1</sub>/TiO<sub>2</sub> significantly increases NO<sub>x</sub> conversion by reducing the energy barrier of H<sub>2</sub> activation. We demonstrate that two H atoms of H<sub>2</sub> molecule are absorbed by adjacent Pt atoms in Pt-O and Pt-Ti, respectively, which can promote the cleave of H-H bonds. Besides, Pt<sub>Ti</sub> sites facilitate the adsorption of NO molecules and further lower the activation barrier of the whole de-NO<sub>x</sub> reaction. Extending the concept to Pt<sub>1</sub>/Nb<sub>2</sub>O<sub>5</sub> and Pd<sub>1</sub>/TiO<sub>2</sub> systems also sees enhanced catalytic activities, demonstrating that engineering the cocatalytic sites can be a general strategy for the design of high-efficiency catalysts that can benefit environmental sustainability.