負膨脹及近零膨脹材料Ca1-xSrxZr4P6O24的制備與拉曼光譜研究.pdf

1、鄭州大學(xué)碩士學(xué)位論文負膨脹及近零膨脹材料Ca1xSrxZr4P6O24的制備與拉曼光譜研究姓名：謝東彥申請學(xué)位級別：碩士專業(yè)：光學(xué)工程指導(dǎo)教師：袁斌；梁二軍201105AbstractAbstractIngeneral，mostmaterialsexpandonheatingandcontractoncoolingTheyexhibitpositivecoefficientsofthermalexpansion(CTE)Howevera

2、nincreasingnumberofmaterialswithnegativethermalexpansion(NTE)havebeendiscoveredinrecentyearsInterestinnegativethermalexpansionmaterialshasincreasedgreatlyinrecentyears，especiallywhenimprovedunderstandingoftheunderlyingat

3、omisticandmolecularmechanisms，aswellasaraftofnewpotentialapplicationsareconcernedTheNaZr2P30i2typestructure(NZP)hasemergedasanewfamilyandhasattractedsignificantattentionduetotheirstabilitytothelowthermalexpansioncoeffici

4、ents，extremeenvironmentalconditions，goodthermalshockresistance，fastionicconductivityandcatalyticactivityOftheNZPmembers，ithasbeenobservedthatCaZr4P6024andSTZr4P6024exhibitanoppositeanisotropyintheirlatticethermalexpansio

5、nsSoitispossibletoobtainnearzeroexpansionmaterialsbymeansofformingthecompositionofmisciblebinarysolidsolutionInthisthesis，lowthermalexpansionceramicsCalxSrxZr4P6024(x=O，05，1)aresynthesizedbyrapidsolidstatereactionsAndals

6、owestudythestructureandphasetransitionsofCalxSrxZr4P6024compoundsbyRamanspectroscopyThephononmodesforsymmetricandasymmetricstretching，symmetricandasymmetricbending，translationalandlibrationalmotionsaleassignedItisshownth

7、attheRamanbandpositionsaleobviouslyaffectedbyCa2orsrcationsduetotheirdifferentcationsizeandelectronicnegativityFormostoftheRamanmodes，theshiftamountswithtemperatureinCa05Sr05Zr4P6024arebetweenthoseinCaZr4P6024andSrgr4P60

8、24，suggestingtheoppositeanisotropicthermalexpansionpropertiesresultedfromCaandsrcancellingeachotherinCao5Sro5Zr4P6024TemperaturedependenceoftheRamanspectroscopicrevealsthatthereisnophasetransitionofallthesamplesfroml13Kt