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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

Thank you