How Rh surface breaks CO<sub>2</sub> molecules under ambient pressure.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 33159056.
- Also identified by DOI 10.1038/s41467-020-19398-1 and PMC identifier 7648795.
- 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
Utilization of carbon dioxide (CO<sub>2</sub>) molecules leads to increased interest in the sustainable synthesis of methane (CH<sub>4</sub>) or methanol (CH<sub>3</sub>OH). The representative reaction intermediate consisting of a carbonyl or formate group determines yields of the fuel source during catalytic reactions. However, their selective initial surface reaction processes have been assumed without a fundamental understanding at the molecular level. Here, we report direct observations of spontaneous CO<sub>2</sub> dissociation over the model rhodium (Rh) catalyst at 0.1 mbar CO<sub>2</sub>. The linear geometry of CO<sub>2</sub> gas molecules turns into a chemically active bent-structure at the interface, which allows non-uniform charge transfers between chemisorbed CO<sub>2</sub> and surface Rh atoms. By combining scanning tunneling microscopy, X-ray photoelectron spectroscopy at near-ambient pressure, and computational calculations, we reveal strong evidence for chemical bond cleavage of O‒CO* with ordered intermediates structure formation of (2 × 2)-CO on an atomically flat Rh(111) surface at room temperature.