Trihydrogen Formation on Gold Nanoparticles in Strong Laser Fields.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 41592788.
- Also identified by DOI 10.1021/acs.nanolett.5c03438 and PMC identifier 12904087.
- 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
The trihydrogen cation (H<sub>3</sub><sup>+</sup>) plays a central role in proton-transfer chemistry, astrochemical pathways, and hydrogen plasma environments, acting as a key indicator of ultrafast proton rearrangement. Although H<sub>3</sub><sup>+</sup> formation has been studied extensively in the gas phase, its surface-mediated generation and its sensitivity to nanoparticle morphology remain largely unexplored. Gold nanoparticles (AuNPs), which can localize surface charge and sustain strong electric fields, offer an ideal platform to probe such nonequilibrium reaction pathways. Using reaction nanoscopy, we spatially map H<sub>3</sub><sup>+</sup> production on AuNPs exposed to intense femtosecond laser fields. By comparing spherical and faceted nanoparticles, we demonstrate how morphology modulates the charge density and governs the reaction efficiency. We find that sharp features on faceted particles concentrate charge more effectively, promoting molecular fragmentation and enabling proton rearrangement and migration that enhance H<sub>3</sub><sup>+</sup> yields. This work opens new directions for exploiting strong-field interactions at metal interfaces to drive nanoscale reactivity and photocatalysis.