Hexagonal network organization of dye-loaded zeolite L crystals by surface-tension-driven auto-assembly

Highly fluorescent dye-loaded zeolite L crystals, measuring approximately 1.4 µm in length and 650 nm in diameter, have been organized in a hexagonal network by a surface tension driven auto-assembly process. A polydimethylsiloxane (PDMS) film presenting a trigonal ordering of spherical protuberances, including a polystyrene (PS) hexagonal network occupying their interstices, was chosen as the platform for a surface tension driven auto-assembly. The overall wettability and the difference of surface tension between PDMS and PS surfaces were found to offer good conditions to order micrometric dye-loaded zeolite L crystals in a two dimensional hexagonal network. The resulting film displays a regular hexagonal pattern of polarized fluorescence reflecting the polarization properties of the dye molecules inserted in the parallel nanochannels of the zeolites.