Preparation And Characterization Of Doped BaTiO₃Thermal Induced Phase Transition Powder

Doped BaTiO3is a kind of perovskite with phase transition character, which has anoutstanding opticle, thermal and electrical properties. It’s in a tetragonal lattice withproperties of conductive under the curie temperature, and it turns to be a cubic phaselattice with properties of insulating above the curie temperature. It has a very broadapplication prospects in the field of thermally induced optoelectronic devices such asthe memory devices, solar cells, thermal devices, etc, which is one of the currentlyhotspots in related fields. Due to the relatively sensitive to size effects, it focuses on theceramic materials of the current research on doped BaTiO3, but few report on the phasetransition character of doped BaTiO3powder.Synthesized Sr, Zr-doped BaTiO3by solid-phase. In the synthesis progress, BaCO3,SrCO3, TiO2and ZrO2powder is used as raw. it is discussed that the effects on theproduct performance caused by the calcination process, the particle size of raw materialpowder, type and content of doping factors.The result shows that, while twice-distilled water is used as milling flour, thethermal-induced phase transition powder is succesfully synthesised with an outstandingrate of spectral reflectance, which reaches90%at400nm~2500nm wavelength. It issynthesised that cubic phase Ba1-xSrxTiO3and BaTi1-xZrxO3powder with particle sizebetween200~500nm in the calcination temperature1100℃. When the calcinationtemperature rises to1450℃, the procuct comes out to be tetragonal lattice Ba1-xSrxTiO3and BaTi1-xZrxO3with particle size between5~10μm.The reaction temperature is efficially redused by using nano-TiO2powder as raw,during the solid-phase process, And the temperature of generation of tetragonal phaseBa1-xSrxTiO3and BaTi1-xZrxO3powder drops about100℃from1450℃to1350℃.The dopping of Sr and Zr to BaTiO3powders is to reduced the temperature ofphase transition. Which means,1%Sr doped into the BaTiO3lattic, the phase transitiontemperature of BaTiO3powder is to move-1.3℃, while1%Zr doped into BaTiO3powder lattic, the phase transition temperature is to move-2℃.With30%Zr doped, When calcined in1450℃for2h, tetragonal phase BaTi0.7Zr0.3O3powder with thermal-induced phase transition properties is synthesised.Its phase transition temperature is30℃, and exhibited a mutation on resistivity.