In situ tuning of electronic structure of catalysts using controllable hydrogen spillover for enhanced selectivity.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 32963236.
- Also identified by DOI 10.1038/s41467-020-18567-6 and PMC identifier 7508871.
- Licence recorded as CC BY.
- The licence permits redistribution, so the abstract is shown in full and the full text is available from the publisher.
Abstract
In situ tuning of the electronic structure of active sites is a long-standing challenge. Herein, we propose a strategy by controlling the hydrogen spillover distance to in situ tune the electronic structure. The strategy is demonstrated to be feasible with the assistance of CoO<sub>x</sub>/Al<sub>2</sub>O<sub>3</sub>/Pt catalysts prepared by atomic layer deposition in which CoO<sub>x</sub> and Pt nanoparticles are separated by hollow Al<sub>2</sub>O<sub>3</sub> nanotubes. The strength of hydrogen spillover from Pt to CoO<sub>x</sub> can be precisely tailored by varying the Al<sub>2</sub>O<sub>3</sub> thickness. Using CoO<sub>x</sub>/Al<sub>2</sub>O<sub>3</sub> catalyzed styrene epoxidation as an example, the CoO<sub>x</sub>/Al<sub>2</sub>O<sub>3</sub>/Pt with 7 nm Al<sub>2</sub>O<sub>3</sub> layer exhibits greatly enhanced selectivity (from 74.3% to 94.8%) when H<sub>2</sub> is added. The enhanced selectivity is attributed to the introduction of controllable hydrogen spillover, resulting in the reduction of CoO<sub>x</sub> during the reaction. Our method is also effective for the epoxidation of styrene derivatives. We anticipate this method is a general strategy for other reactions.