Improvement in the emission properties of a luminescent anionic dye intercalated between the lamellae of zinc hydroxide-layered

A luminescent green anionic dye, 8-hydroxypyrene-1,3,6-trisulfonic acid trisodium, has been intercalated between the layers of the zinc hydroxide-layered (here named as ZHL-layered-NO3) using an anion exchange technique to produce new luminescent organic–inorganic hybrid materials with interesting photoemission properties. X-ray diffraction, FTIR, UV–vis spectroscopic and scanning electron microscopic studies have shown the incorporation of the luminescent anionic dye between the layers of the inorganic host. X-ray diffraction studies revealed increases in the basal spacing of ZHL-layered hybrid after the intercalation of the green dye using different time intercalation. The interlayer spacing increased from 0.98 nm in the pristine ZHL-layered NO3 to 3.54, 3.18 and 3.62 nm in the ZHL-layered/Py-SO3−3 composites at 12, 24 and 48 h of time intercalation, respectively. Photophysical properties of these new luminescent hybrids (ZHL-layered/Py-SO3−3) were also investigated using the UV–vis absorption, steady-state and dynamic fluorescence spectroscopies. All hybrid materials presented UV–vis absorption bands and photoemission at green region due to the presence of the anionic dye in the galleries of the inorganic layered. For the material produced at 12 h of time intercalation, a higher quantum yield photoluminescence (ϕPL = 13.0%) was observed compared to the pure dye solid (ϕPL = 1.0%). This result was attributed to the confinement of the anionic species in the host two-dimensional gallery. These observations open new opportunities for the use of this organic dye immobilized in alternative layered compound for electronic devices or for sensors.