X ‐Ray‐Induced Growth Dynamics of Luminescent Silver Clusters in Zeolites

Luminescent silver clusters can be formed in zeolite frameworks by X ‐ray irradiation, but they have a broader size distribution. Cluster growth dynamics is framework‐dependent and is also dependent on degree of silver loading in the framework. Growth from cations to luminescent clusters then non‐luminescent metallic nanoparticles is observed. AbstractHerein, AlKα X ‐rays are used to drive the growth of luminescent silver clusters in zeolites. The growth of the silver species is tracked using Auger spectroscopy and fluorescence microscopy, by monitoring the evolution from their ions to luminescent clusters and then metallic, dark nanoparticles. It is shown th at the growth rate in different zeolites is determined by the mobility of the silver ions in the framework and that the growth dynamics in calcined samples obeys the Hill–Langmuir equation for noncooperative binding. Comparison of the optical properties of X‐ray‐grown silver clusters with silv er clusters formed by standard heat treatment indicates that the latter have a higher specificity toward the formation of luminescent clusters of a specific (small) nuclearity, whereas the former produce a wide distribution of cluster species as well as larger nanoparticles.

Source: Small - July 1, 2020 Category: Nanotechnology Authors: Oliver Fenwick, Eduardo Couti ño‐Gonzalez, Fanny Richard, Sara Bonacchi, Wouter Baekelant, Dirk Vos, Maarten B. J. Roeffaers, Johan Hofkens, Paolo Samorì Tags: Full Paper Source Type: research