Dye-Loaded Zeolite L Sandwiches as Artificial Antenna Systems for Light Transport

Abstract

The synthesis and characterization of dye loaded zeolite L sandwiches acting as artificial antenna systems for light harvesting and transport is reported. A set of experimental tools for the preparation of neutral dye-zeolite L materials ranging from low to maximum packing densities has been developed. The role of co-adsorbed water and the distribution of molecules between the inner and the outer surface were found to be the determining parameters. p-Terphenyl (pTP) turned out to be very suitable for studying these and other relevant parameters of neutral dye-zeolite L materials. We observed that pTP located in the channels of zeolite L can reversibly be displaced by water. This can be used when synthesizing such materials. We also observed that all-trans-1,6-diphenyl-1,3,5-hexatriene (DPH) which is very photolabile in solution is stable after insertion into zeolite L. By combining our extensive knowledge of these systems with ionexchange procedures developed in an earlier study, we have realized the first bi-directional three-dye antenna. In this material the near UV absorbing compounds DPH or 1,2-bis-(5-methyl-benzoxazol-2-yl)-ethene (MBOXE) are located in the middle part of zeolite L nanocrystals followed on both sides by pyronine (Py) and then by oxonine (Ox) as acceptors. Fluorescence of the oxonine located at both ends of the cylindrical zeolite L crystals was observed upon excitation of the near UV absorber in the middle section at 353 nm, where neither oxonine nor pyronine absorb a significant amount of the excitation light.

Tuning the Size and Shape of Zeolite L-Based Inorganic-Organic Host-Guest Composites for Optical Antenna Systems

“…[29] Data on water desorption measurements of different zeolite L materials have recently been reported. [30] The inner pore volume can be determined from adsorption measurements with, e.g., H 2 O, N 2 , Ar, O 2 , Kr. [1] The specific surface area and the free pore volume of zeolite L are best determined by means of Ar adsorption at 87 K. Experiments should be carried out at small relative pressure and in small steps with sufficiently long waiting periods to make sure that equilibrium conditions are maintained.…”

Light‐Harvesting Antennae

“…Zeolite L is a crystalline alumosilicate in which the SiO 4 and AlO 4 tetrahedra give rise to one-dimensional channels arranged in a hexagonal structure. If the three dyes are suitably chosen, light excitation of dye1 located in the middle part leads to energy-migration processes on both sides of the channels giving rise to the sensitized emission of dye3 [108]. Crystals of defined dimension in the size from 30 to 3000 nm can be obtained.…”

Fluorescent Hydroxyflavone–Zeolite Nanoparticles: Ship‐in‐a‐Bottle Synthesis and Photophysical Properties

“…The incorporation of organic dye molecules in organic,1 inorganic,2 or hybrid3 hosts is of particular interest in many different areas of materials and analytical chemistry. Potential fields of application include the development of photonic devices and materials such as waveguide laser cavities,4 optical memory systems,5 electroluminescent devices,6 artificial antenna systems,7 radiation detectors,8 optical switches,9 as well as the construction of optical sensors 10. Among host–guest assemblies, zeolites and zeolitic molecular sieves have proved to be very convenient hosts 11…”