Photo-induced modifications of the substrate-adsorbate interaction in K-loaded porous glass

TL;DR

This study explores how visible and infrared light influence potassium atoms in nanoporous glass, revealing light-specific effects on atomic mobility, cluster formation, and substrate interactions in confined nanosystems.

Contribution

It demonstrates that visible light enhances atomic diffusion and nanoparticle formation, while infrared light modifies substrate interactions and cluster dynamics, providing new insights into photo-induced effects in nanoconfined systems.

Findings

Visible light promotes atomic mobility and nanoparticle formation.

Infrared light alters substrate properties and cluster dynamics.

Infrared irradiation affects nanoparticle populations even after illumination.

Abstract

The effects of visible and infrared light on potassium atoms embedded in a nanoporous glass matrix are investigated. Photodesorption by visible light enhances the atomic mobility and causes the formation of metallic nanoparticles. Two different populations of metastable clusters with absorption bands in the near-infrared and infrared are grown as a consequence of illumination. Atoms can move between the two groups through sequences of adsorption/desorption events at the pore surface. Irradiation with infrared light, instead, does not significantly enhance the atomic diffusion inside the pores. However, it induces relevant modifications of the substrate, thus changing its interaction with the assembled clusters. Consequently, infrared light alters the dynamics of the system, affecting also the evolution of non-resonant nanoparticles populations, even after the illumination sequence. These results provide new insights on the photo-induced modifications of the substrate-adsorbate interaction in nano-sized confined systems.