using combinatorial and multidisciplinary approaches the exact nature of luminescent silver clusters in LTA zeolites was unraveled by X-ray-excited optical
luminescence-EXFAS (XEOL-EXAFS), DFT, and photoluminescence experiments
[81]. This task had remained elusive for over more than four decades; therefore, this
report may pave the way for the development of rational design rules for confining
luminescent silver and other metal clusters in zeolites.
2.4 Tailoring the Optoelectronic Properties of Silver Clusters
Confined in Zeolites
The versatility of the Ag-zeolite multicomponent system is directly related to the
intrinsic and complex tunability of the system as a whole [82]. There are several key
zeolite parameters, which confer peculiar optical properties to the clusters, such as,
the framework Si/Al ratio, choice of counter-balancing ions, silver loading, and
zeolite topology (Fig. 2). De Cremer and collaborators systematically evaluated the
effect of zeolite topology, silver loading, and counter-balancing cation on the
luminescence color displayed by Ag-LTA and Ag-FAU zeolites, observing that
green and red emitters were mainly found in Ag-LTA zeolite, whereas for
Ag-FAU samples green and yellow emitters were observed [19]. Later, the external
quantum efficiency (EQE) of Ag-LTA and Ag-FAU samples was evaluated,
Fig. 2 Synthesis strategy (highlighting the main parameters) utilized to confine and characterize
luminescent silver clusters in zeolites
86
E. Coutino-Gonzalez et al.
luminescence-EXFAS (XEOL-EXAFS), DFT, and photoluminescence experiments
[81]. This task had remained elusive for over more than four decades; therefore, this
report may pave the way for the development of rational design rules for confining
luminescent silver and other metal clusters in zeolites.
2.4 Tailoring the Optoelectronic Properties of Silver Clusters
Confined in Zeolites
The versatility of the Ag-zeolite multicomponent system is directly related to the
intrinsic and complex tunability of the system as a whole [82]. There are several key
zeolite parameters, which confer peculiar optical properties to the clusters, such as,
the framework Si/Al ratio, choice of counter-balancing ions, silver loading, and
zeolite topology (Fig. 2). De Cremer and collaborators systematically evaluated the
effect of zeolite topology, silver loading, and counter-balancing cation on the
luminescence color displayed by Ag-LTA and Ag-FAU zeolites, observing that
green and red emitters were mainly found in Ag-LTA zeolite, whereas for
Ag-FAU samples green and yellow emitters were observed [19]. Later, the external
quantum efficiency (EQE) of Ag-LTA and Ag-FAU samples was evaluated,
Fig. 2 Synthesis strategy (highlighting the main parameters) utilized to confine and characterize
luminescent silver clusters in zeolites
86
E. Coutino-Gonzalez et al.