Photoluminescence properties of Eu3+-exchanged zeolite L crystals annealed at 700 °C

Abstract

Herein we describe the change in emission color of Eu³⁺-exchanged zeolite L (Eu³⁺/ZL) crystals annealed at 700 °C by changing the solvents used in the washing step during preparation procedure. It has been revealed that washing Eu³⁺/ZL crystals with deionized water leads to materials emitting a strong violet-blue emission, whereas washing with ethanol can give Eu³⁺/ZL crystals bright red luminescence. The obtained Eu³⁺/ZL crystals were characterized by using SEM, XRD, XPS and TG techniques, and the luminescence feature was studied with photoluminescence spectroscopy. XPS result suggests that some of the Eu³⁺ ions are reduced to Eu²⁺ ions during the annealing process. TG and decay curves reveal that more water molecules can be found in the water-washed Eu³⁺/ZL crystals compared to those washed with ethanol.