Enhancement of upconversion, temperature sensing and cathodoluminescence in the K+/Na+ compensated CaMoO4:Er3+/Yb3+ nanophosphor. (25th May 2017)

• Record Type: Journal Article
• Authors: Sinha, Shriya; Mahata, Manoj Kumar; Swart, H. C.; Kumar, Ashwini; Kumar, Kaushal
• Is Part Of: New journal of chemistry. Volume 41:Number 13(2017)
• Page Start: 5362
• Page End: 5372
• Publication Date: 2017-05-25
• Subjects: Chemistry -- Periodicals; Chimie -- Périodiques; 540
• DOI: 10.1039/c7nj00086c
• Languages: English
• ISSNs: 1144-0546

Abstract

Abstract : Enhancing upconversion, temperature sensing and cathodoluminescence in the CaMoO4 :Er 3+ /Yb 3+ nanophosphor via K + /Na + simultaneous codoping. Abstract : Charge compensated alkali metal ions (Na +, K + ) codoped CaMoO4 :Er 3+ /Yb 3+ nano-flakes were synthesized via a hydrothermal method. The effect of doping concentration of Na + and K + ions on upconversion luminescence in CaMoO4 :Er 3+ /Yb 3+ was investigated with respect to its dependence on input pump power and external temperature using 980 nm laser light excitation. Simultaneous incorporation of K + /Na + into CaMoO4 :Er 3+ /Yb 3+ showed 36 and 5 times enhancements in green and red emission intensities, which were explained in terms of charge compensation and lifetime variation in the 4 S3/2 and 4 F9/2 levels of Er 3+ ions. A high thermal sensitivity of the material was realized with K + /Na + incorporation using the fluorescence intensity ratio technique of two thermally coupled energy levels ( 2 H11/2 & 4 S3/2 ) of Er 3+ . The temperature sensitivity was enhanced by four times by K + /Na + codoping with a maximum sensitivity of 0.0216 K −1 at 490 K. Additionally, the cathodoluminescence properties of the material as a function of filament current and accelerating voltage were also explored and showed enhanced luminescence, which is suitable for field emission display device applications. The results show that simultaneous codoping of K + /Na + in CaMoO4 :Er 3+ /Yb 3+ is a very effective way to integrate this material for advanced photonic applications.