Ce-doped YAG single-crystals prepared by continuous wave (CW)–CO2 laser combustion technique with attractive characteristics and moderate white LED performance. (December 2020)

• Record Type: Journal Article
• Authors: Abd, Husnen R.; Hassan, Z.; Ahmed, Naser M.; Thahab, S.M.; Alsultany, Forat H.; Omar, A.F.
• Is Part Of: Optics & laser technology. Volume 132(2020)
• Publication Date: 2020-12
• Subjects: Continuous wave –CO2 laser technique -- Yttrium aluminum garnet -- Ce4+, luminous efficiency of radiation -- White LED -- Standard CIE 1931 chromaticity diagram; Optics -- Periodicals; Lasers -- Periodicals; Electronic journals; 621.366
• DOI: 10.1016/j.optlastec.2020.106506
• Languages: English
• ISSNs: 0030-3992

Abstract

Highlight: YAG:Ce 3+ phosphor was synthesized in just 1.5 min by new combustion technique using CO2 laser beam. The as-prepared ceramic displayed a direct pure YAG:Ce 3+ phase with moderate performances of the white LED device. Sintering temperature played a pivotal role in YAG:Ce 3+ luminescence properties. Performances of the blue InGaN-based WLEDs as a function of the sintering temperature were also explored. Various white colours LED devices was obtained. Abstract: In this work, the influence of continuous wave –CO2 laser-induced solution combustion as a new and effective technique to prepare YAG:Ce phosphor was investigated. The as-prepared ceramic displayed a direct pure YAG phase within the laser exposure time of 1.5 min with an attractive characteristics and moderate white light-emitting diode (WLED) performance, suggesting that laser synthesis has a role to play in accelerating the diffusion of the cations and an increase in reaction rate. However, the thermal treatment step plays a key role to adjust efficient luminescence processes. In addition, the luminescence properties were strongly dependent on the sintering strategies due to the expulsion of defects (e.g. CeO2 and other impurity phases) from matrix. We showed experimentally that increasing the luminescence intensity has an effect observed on the CIE chromaticity parameters and the theoretically calculated luminous efficiency of radiation (LER). This work presents the effects of thermal treatment properties on the YAG host lattice and explains the mechanism of YAG formation under CO2 laser beam.