Luminescent properties of ZSM-5 zeolite phosphor and its application to aquatic plant lighting and white LEDs

Abstract

In order to explore ideal materials with suitable excitation wavelengths, high thermal stability and good emission characteristics for phosphor-converted white light emitting diodes (pc-WLEDs), in this work, a blueish-white phosphor (λex = 390 nm) was realized by a new strategy of carbocations formation in ZSM-5 zeolite, which maintains the luminescence intensity at 473 K is 103% of that at room temperature. Following immersion in ethanol, water, 40 wt% sodium hydroxide solution (NaOH), and concentrated hydrochloric acid (HCl) for 120 h, the luminescence intensity was maintained at 92%, 87%, 80%, and 82% of the normal state, respectively. By packaging the sample on a near-ultraviolet (NUV) chip (390 nm), a blueish-white pc-LED was fabricated, which has a promising commercial prospect in the field of aquatic plant lighting. Meanwhile, a pc-WLED device was fabricated by combining a 390 nm NUV chip and ZSM-5 zeolite and red phosphor K2MgGeO4:Eu3+. It has an excellent property with the correlated color temperature (CCT) = 4600 K and color rendering index (CRI) = 91.5, indicating that ZSM-5 zeolite has good application prospects in the pc-WLEDs field.