Tuning the energetics and tailoring the optical properties of silver clusters confined in zeolites

Abstract

The integration of metal atoms and clusters in well-defined dielectric cavities is a powerful strategy to impart new properties to them that depend on the size and geometry of the confined space as well as on metal-host electrostatic interactions. Here, we unravel the dependence of the electronic properties of metal clusters on space confinement by studying the ionization potential of silver clusters embedded in four different zeolite environments over a range of silver concentrations. Extensive characterization reveals a strong influence of silver loading and host environment on the cluster ionization potential, which is also correlated to the cluster's optical and structural properties. Through fine-tuning of the zeolite host environment, we demonstrate photoluminescence quantum yields approaching unity. This work extends our understanding of structure-property relationships of small metal clusters and applies this understanding to develop highly photoluminescent materials with potential applications in optoelectronics and bioimaging.

Interaction between the exchanged Mn2+ and Yb3+ ions confined in zeolite-Y and their luminescence behaviours

“…It can be seen that the coordination peak of Yb-O becomes weaker while that of Yb-Cl tends to show up and gradually be enhanced as the content of Mn 2+ increases. The Cl − introduced by [MnCl] presents at the vicinity of Yb 3+ only beyond certain contents of Mn 2+ in the samples, which is ascribed to that the cation-cation repulsion hinders a new cation to be absorbed inside the cavity of the zeolite3536. However, both the two peaks shift to the smaller value when the Mn 2+ content x reaches 0.6, which is likely caused by the partial collapse or densification of zeolite-Y framework.…”

“…The structural defects would act as killing center of energy and make the Mn 2+ luminescence decay faster(quenched). According to the most recent reports, cation-cation repulsion would prevent more cations to enter the pores of the zeolite3536, especially for the higher valent Yb 3+ and Mn 2+ ions exchanging the original cation with +1 valence. With elevating the Mn 2+ contents, aggregation in the atomic scale might take place35, which reduces the amount of defects.…”

Silver-induced reconstruction of an adeninate-based metal–organic framework for encapsulation of luminescent adenine-stabilized silver clusters

“…Furthermore the so-called modified Auger parameters 84 calculated from the XPS data are characteristic of small silver clusters. 85,86 Photoelectron spectroscopy in air (PESA) showed ionisation energies of the silver-transformed MOFs of 5.62 ± 0.05 eV and 5.52 ± 0.11 eV, with these values probably coming from the MOF framework itself (5.30 ± 0.04 eV before transformation) or possibly the silver clusters, but certainly not from metallic silver whose work function is about 4.3 eV. 87 …”

Facile Two‐Step Synthesis of All‐Inorganic Perovskite CsPbX3 (X = Cl, Br, and I) Zeolite‐Y Composite Phosphors for Potential Backlight Display Application

“…[33] Porous zeolites are an especially interesting host to encapsulate and stabilize perovskite QDs, because the resulting micrometer-sized composites would be directly compatible with mature packaging techniques for commercial WLEDs. [35][36][37][38] Zeolites have been demonstrated to improve and stabilize emission from various types of luminescent centers including metal ions, [35,36,[39][40][41][42] nanoclusters, [38,[43][44][45][46][47] organic complexes, [48,49] and semiconductor QDs. [34] They can accommodate a variety of chargebalancing cations that are readily exchangeable.…”

“…[53] Among the various kinds of zeolites, zeolite-Y with the faujasite structure has been studied as a host for luminescent chalcogenide QDs. [38] Here, we report a successful two-step synthesis method for perovskite QDs embedded in zeolite-Y. Perovskites are a ternary material, so control over the diffusion and reaction of three types of ions is necessary.…”