Enhanced upconversion emission and temperature sensor sensitivity in presence of Bi3+ ions in Er3+/Yb3+ co-doped MgAl2O4 phosphor. Issue 8 (1st June 2018)

• Record Type: Journal Article
• Authors: Choudhary, A.K.; Dwivedi, A.; Bahadur, A.; Yadav, T.P.; Rai, S.B.
• Is Part Of: Ceramics international. Volume 44:Issue 8(2018)
• Page Start: 9633
• Page End: 9642
• Publication Date: 2018-06-01
• Subjects: Inorganic phosphor -- Rare earth -- Alkaline earth-aluminate -- Temperature sensing -- Laser induced optical heating; Ceramics -- Periodicals; Céramique industrielle -- Périodiques; Ceramics; Periodicals; Electronic journals; 666
• DOI: 10.1016/j.ceramint.2018.02.190
• Languages: English
• ISSNs: 0272-8842

Abstract

Abstract: Mg0(.95-x) Erx Yb0.05 Al2 O4 (x = 0.3, 0.5, 0.7, 1.0, and 1.5 mol%) and Mg(0.943-y) Er.007 Yb0.05 Biy Al2 O4 (y = 2, 5, 7, 10, and 15 mol%) phosphor samples have been synthesized by solid state reaction method. The X-ray diffraction (XRD) measurements confirm the cubic phase formation and shift in peaks position due to Bi 3+ ions doping. The surface morphology of the prepared samples has been studied by scanning electron microscopy (SEM) measurement. The FTIR spectra reveal the information about the vibrational bands arising due to different molecules or species/groups. The Mg(0.943-y) Er0.007 Yb0.05 Al2 O4 phosphor sample gives an intense upconversion (UC) green emission peaks centered at ~ 521 and 543 nm due to ( 4 S3/2, 2 H11/2 )→ 4 I15/2 transitions and the weak red emission at 660 nm due to 4 F9/2 → 4 I15/2 transition. The emission intensity of green bands is enhanced by 30 times and the red band by 10 times on addition of Bi 3+ in Mg (0.943) Er0.007 Yb0.05 Al2 O4 phosphor. This increase in emission intensity also enhances the fluorescence intensity ratio (FIR) of two thermally coupled levels emitting green radiation (i.e. FIR = I521 /I543 ). The large variations of FIR with temperature clearly suggest that the material can be used as temperature sensor. The temperature sensing sensitivity is found to be quite high in presence of Bi 3+ ions. The laser induced optical heating with pump power has also been observed in this material.