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II INTERNATIONAL SCIENTIFIC CONFERENCE OF YOUNG RESEARCHERS 

64 

 Qafqaz University                         

          18-19 April 2014, Baku, Azerbaijan 

OBTAINING AND INVESTIGATION LUMINESCENT PROPERTIES OF          

Ca

x

Ba

1-x

Ga

2

S

4

: Eu, Ce SOLID SOLUTIONS  

 

Tural NAGHIYEV 

Institute of Physics of Azerbaijan National Academy of Sicences 

[e-mail] 

AZƏRBAYCAN 

 

Thiogallates type BaGa

2

S

4

 and CaGa

2

S

4

, activated earth ions widely investigated since the 70s until to this day [1]. 

Due to the interesting optical and luminescent properties, they are widely used in various fields of science and technology. 

Due to the  interesting optical and luminescent properties, they are widely used in various areas of science and technology, 

in particular, in a display device, energy saving light sources [2]. Recently, conducted investigation of the properties of the 

mixed compounds MGa

2

S

4

 - M'Ga

2

S

4

 (M and M '= Ca, Sr, Ba - alkaline earth elements) doped with rare earth elements [3]. 

In ternary systems MGa

2

S

4

-M'Ga

2

S

4

 produced isovalent solid solutions of varying lengths from continuous to limited with a 

large difference in the ionic radii (0.99 ÷ 1.35Å) divalent cations. In this work as the objects of the investigation alloyed 

Eu

2+

 and Ce

3+

 compounds, in the system CaGa

2

S

4

-BaGa

2

S

4

. The aim of this research is to obtain and investigation structural 

and luminescent properties of  Сa

x

Вa

1-x

Ga

2

S

4

: Eu, Ce (0,1≤х≤0,9) crystals, having unlimited isomorphous substitution of 

alkaline earth cations to determine the possibility of using them as phosphors for display devices, high-brightness white 

LEDs.  

Сa

x

Вa

1-x

Ga

2

S

4

: Eu, Ce (0,1≤х≤0,9) solid solutions were obtained by solid state reaction from the BaS, CaS, Ga

2

S

3

 

binary comounds taken in stoichiometric ratios. Synthesis was carried out in quartz ampoules evacuated to 10

-4

 Torr in 

single-temperature furnace at 1000

0

S for 1 h. After synthesis, the resulting compounds exposed annealing for 4h. at 800

0

S. 

Alloying of rare-earth ions Eu

2+

, Ce

3+

 carried out by addition into the charge of synthesized solid solutions in the form of 

EuF

3

 and CeF

3

. Investigations were carried out on installations HR-460 spectrometer. The sources of excitation 

photoluminescence (PL) is a continuous helium-cadmium laser (λ

ext

 = 325 nm), LED (λ

ext

 = 367 nm) and xenon lamp.  

We were investigated photoluminescence spectra (from 10K to 300K temperature range) and photoluminescence 

excitation, intensity dependencies, the half-width of the PL bands on the composition x and temperature specified for 

Ca

x

Ba

1-x

Ga

2

S

4

: Eu

2+

 and Ce

3+

 (x = 0,1 ÷ 0,9), activation energy of thermal quenching, Stokes shift, Juan – Rice factor. 

Literature 

1.  Peters T., Baglio J. Luminescence and Structural Properties of Thiogallate Ce

3+

 and Eu

2+

activated Phosphors  //J. Electrochem. Soc. 

1972, v. 119,No 2, p.230-236  

2.  Sun S-S. and Tuenge R.T., Kane J. and Ling. M. Electroluminescence and Phototluminescece of  Cerium_Activated Alkline Earth 

Thiogallate Thin films and Devices. // J. Electrochem. Soc., 1994, Vol. 141, 10, p.2877-2883. 

3.  Ki-Young Ko, Young-Duk Huh, and Young Rag Do .Cathodoluminescence and Longevity Properties of Potential Sr

1-x

M

x

Ga

2

S

4

:Eu 

(M = Ba or Ca) Green Phosphors for Field Emission DisplaysBull. KoreanChem. Soc. 29 (2008) 822 – 826.