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SYNTHESIS AND CHARACTERISATION OF
CERIUM DOPED STRONTIUM BARIUM NIOBATE NANO
CERAMIC POWDER SYSTEM
BLUE PHOSPHORNANO SIZE APPLICATIONS
AIM
APPLICATIONS
Holographic information recording.Used as blue phosphor for lighting .Display devicesLed
STRONTIUM BARIUM NIOBATE
SBN chemical formula SrxBa(1-x)Nb2O6 , x=0.5Structure of sbnTetragonal TungstenBronze structureFerroelectrc materialIts structural formula is (A1)4(A2)2C4(B1)2(B2)8O30
A1-pentagonol,A2-tetragonal, C-trigonal
PREPARATION OF SBN
Sol-gel method AdvantagesLow temperatureHomogenityBetter control of structure
EXPERIMENTAL METHOD
Sr-EDTA solution
Barium nitrate
Citric acid (molar ratio of CA:Nb=3:1)
Nb-citrate solution
NH3.nH2O (pH=8)
EDTA aqueous solution EDTA aqueous solution Citric acid aqueous solution
Ba-EDTA solution
Precursor solution
Drying at 800C
Precursor gel
Heat treatment at 8000C
Strontium nitrate Nb2O5.nH2O
CHARACTERISATION OF CERIUM DOPED SBN
XRDIR
XRD
The Debye-Scherrer Method Equation to find Crystallite
Size t= 0.9*λ / βcosθ
IR
FTIR spectroscopy is a technique that provides information about the chemical bonding or molecular structure of materials . The absorption peak associated with Sr-O, Ba-O and Nb-O between 500 and 850 cm-1 are prominent.
ABSORPTION SPECTRUM OF CERIUM DOPED SBN
ABSORPTION SPECTRUM
In order to measure the amount of light absorbed by the sample at room temperature, the samples were excited from 200 nm to 700 nm wavelengths at room temperature
(αhν)1/2 = A[hν- Eg]Band gap of cerium doped SBN=3.2ev
EMISSION SPECTRUM
Electronic configuration of cerium (Z = 58) 4f25d06s2
CONCLUSION
BLUE EMITTER IS MADE
STRUCTURE OF SBN UNCHANGED
OPTICAL PROPERTY CHANGES
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