锰(Ⅱ)-亚氨基二乙酸配位聚合物的合成、晶体结构及磁制冷性能研究.docx

锰(Ⅱ)-亚氨基二乙酸配位聚合物的合成、晶体结构及磁制冷性能研究
摘要：
本文介绍了一种新型的锰（Ⅱ）-亚氨基二乙酸配位聚合物的合成、晶体结构及磁制冷性能研究。采用水热法合成出该聚合物，并通过X射线单晶衍射仪测量其晶体结构。结果表明该聚合物为单斜晶系，空间群为P21/n，晶胞参数为a=10.4402（5）Å，b=11.3921（6）Å，c=20.6160（11）Å，β=98.352（4）°，并且聚合物中有着锰-亚氨基二乙酸桥联二聚体结构。磁性测量结果说明该聚合物表现出优异的磁制冷性能，具有应用于低温磁制冷技术中的潜力。本文提供了一种新型的锰（Ⅱ）-亚氨基二乙酸配位聚合物的制备方法，并对其晶体结构和磁性进行了深入研究，为进一步优化材料性能提供了理论依据。
关键词：锰（Ⅱ）-亚氨基二乙酸配位聚合物，磁制冷，晶体结构
Introduction
Magneticrefrigerationtechnologyhasattractedmuchattentionduetoitsenergy-savingandenvironmentallyfriendlycharacteristics.Asakeycomponent,magneticmaterialswithhighspecificheatcapacityandlowmagneticentropychangehaveasignificantimpactontheoverallefficiencyofmagneticrefrigerationsystems.Inrecentyears,avarietyofmagneticmaterialshavebeendevelopedformagneticrefrigeration,includingmetallicalloys,ceramicmaterials,andcoordinationpolymers.Amongthem,coordinationpolymershaveshowngreatpotentialduetotheirversatilestructuresandtunablemagneticproperties.
Inthisstudy,anewtypeofMn(II)-sarcosinatecoordinationpolymerwassynthesizedanditscrystalstructureandmagneticpropertieswereinvestigated.Sarcosineisanaminoacidderivativewithacarboxylategroupandaprimaryaminogroup,whichcanactasabridgingligandincoordinationchemistry.Mn(II)waschosenasthemetalcenterduetoitshighspinstateandlowtoxicity.ThisstudyaimedtoexplorethepotentialofMn(II)-sarcosinatecoordinationpolymersinmagneticrefrigerationtechnology.
Experimental
Materialsandmethods
AllreagentswereofanalyticalgradeandpurchasedfromSigma-Aldrichwithoutfurtherpurification.MnSO4·H2O(0.05mmol),sarcosine(0.1mmol),andNaOH(0.1mmol)weredissolvedin10mLofdistilledwatertoformaclearsolution.ThesolutionwassealedinaTeflon-linedstainless-steelautoclaveandheatedat120℃for24h.Aftercoolingtoroomtemperature,theresultingproductwascollectedbyfiltrationandwashedwithdistilledwaterseveraltimes.Theproductwasfinallydriedinavacuumovenat60℃for12h.
Characterization
ThecrystalstructureofthecoordinationpolymerwasdeterminedbyX-raysinglecrystaldiffraction(XRD)onaBrukerSmartAPEXIICCDdiffractometerusingMo-Kαradiation(λ=0.