文档名：质子导体电解质钇掺杂锆酸铈钡微波烧结制备及其电化学和力学性能
摘要：质子陶瓷燃料电池(PCFC)是新一代固体氧化物燃料电池(SOFC)技术的重要发展方向.钇掺杂锆酸铈钡BaZr1-x-yCexYyO3-δ(BZCY)是常用的质子导体电解质材料.然而,BZCY电解质致密化通常需要在超过1700℃的高温烧结5h以上,这不仅会消耗大量能源和时间成本,而且,由于制备温度高,当电解质冷却到室温时,残余应力可能会导致试样后期力学破坏,进而影响其力学性能.本研究探索了质子导体电解质BaZr0.7Ce0.2Y0.1O3-δ(BZCY721)的微波烧结工艺及研究了其电化学和力学性能.结果表明:相对于传统烧结方式,微波烧结可以将BZCY721烧结温度降低100～150℃.试样在1500℃微波烧结40min,致密度可以达到97%以上.试样在650℃测试温度下,晶粒阻抗为34.81Ω·cm2,晶界阻抗为89.98Ω·cm2,电导率为6.41×10-4S?cm-1.力学性能测试结果表明,微波烧结的电解质具有与传统烧结结果相当的弹性模量(190.8GPa),以及更优的硬度(12.379GPa)和断裂韧性(0.359MPa·m1/2).本研究结果为在低温下制备致密BZCY721电解质的进一步研究提供了重要参考.
Abstract：IntroductionSolidoxidefuelcell(SOFC),asanefficientandenvironmentallyfriendlyenergyconversiondevice,hasattractedmuchattentionduetoitsnumerousadvantages,i.e.,highelectricalefficiency,lowemissions,andhighfuelflexibility,comparedtootherpowergenerationtechnologies.ToaddressthedegradationissuesfacedbySOFCsoperatingathightemperatures,developingproton-conductingelectrolytesasanalternativetooxygen-conductingelectrodesisrecognizedasaneffectivestrategytolowertheoperatingtemperatureofSOFCs.BZCY721(BaZr0.7Ce0.2Y0.1O3-δ),aproton-conductingelectrolytematerialusedinprotonicceramicfuelcells(PCFCs),exhibitsbothhighprotonconductivityandexcellentchemicalstabilityatlowertemperatures.However,sinteringtheBZCYmaterialtypicallyrequireshightemperaturesexceeding1700℃forover4-5h,resultinginsignificantenergyconsumptionandresidualstressinducedfailuresofcomponents.ItisthusimperativetoexploreadvancedsinteringtechnologytofabricatetheBZCYelectrolytematerials.Microwavesinteringisafield-assistedsinteringtechniquethatutilizestheheatgeneratedbytheinteractionbetweenthespecificmicrowavebandandthemicrostructureofthematerialtoheattheentirematerial,therebyachievingthedesireddensity.Thismethodeffectivelyreducesthesinteringtemperatureandsignificantlyshortensthesinteringtime.MethodsCommercialBZCY721powderandNiOpowderweremixedatamassratioof20:1,andgroundinaballmillfor24htoobtainahomogeneousmixedpowder.Subsequently,themixedNiO-BZCY721powderwasblendedwitha10%PVAsolutionatamassratioof10:1forwetgranulation.Thegranulatedpowderof0.8gwasweightedandpressedintoadiewithadiameterof15mmat350MPafor30s.Thisprocessyieldedcircularspecimenswiththediameterof15mmandthethicknessofapproximately1mm.Theexperimentwasrepeatedtoproduceseveralsetsofgreensamples.Thesampleswerecategorizedintotwogroupsfortraditionalsinteringandmicrowavesinteringexperiments,respectively.Thesamplesfromthetraditionalsinteringgroupwereplaceddirectlyintoaboxfurnacefordebindingandsintering.Thedebindingprocesswascarriedoutatarateof1℃/minto400℃,for2h,thenheatingat5℃/minto1600℃for6h,andfinallycoolingat5℃/minto500℃beforenaturallycoolingtoroomtemperature.Incontrast,thesamplesfromthemicrowavesinteringgroupunderwentthesamedebindingprocessintheboxfurnacebutwerethentransferredtoamicrowavesinteringfurnaceforsinteringatdifferenttemperaturesandholdingtime.Themechanicalpropertiesandelectrochemicalpropertiesofthesamplespreparedusingtwosinteringmethodswereinvestigated.ResultsanddiscussionBasedontheresultsbytheArchimedesmethod,thedensityofsamplespreparedbybothtraditionalsinteringandmicrowavesinteringexceeds96%.Thescanningelectronmicroscopyimagesrevealthatthesamplesbothexhibitahighdegreeofdensity.Thegrainsizedistributionisrelativelyuniform.Thestatisticalanalysisofthegrainsizedistributiondemonstratesthatasthemicrowavesinteringtemperatureincreases,theoverallgrainsizeoftheresultingsampledecreases,becomingmoreuniform.Theaveragegrainsizeofthesamplesinteredbymicrowavemethodat1500℃is0.49μm,whereastheaveragegrainsizeofthesamplesinteredbytraditionalmethodis0.53μm.TheimpedanceanalysisrevealsthatthereisaminimalvarianceintheimpedanceoftheBZCYelectrolyteproducedbybothsinteringtechniqueswhentheoperatingtemperatureremainsbelow500℃.However,oncethetemperaturesurpasses500℃,theimpedanceofthesamplesinteredbymicrowavemethodexceedsthatofthesamplesinteredtraditionalmethod.Thisindicatesthatthemicrowavesinteredsampleexhibitsagreatersensitivityatdifferentoperatingtemperatures,resultinginhigherimpedancevaluesatelevatedtemperatures.Amongthesamples,theconductivitypeakedinthesamplesinteredbytraditionalmethodat1600℃for6hreachesamaximumvalueof1.01×10-3S·cm-1at650℃.Meanwhile,thesamplesinteredat1500℃for40minexhibitsaconductivityof6.41×10-4S·cm-1at650℃.Notethattheactivationenergyassociatedwithmicrowavesinteringconductivityisonly1.071eV.Thesamplesinteredbymicrowavemethodat1500℃for40minexhibitsthemaximumhardness(i.e.,anaveragevalueof12.379GPa).Thesamplesinteredbytraditionalmethodat1600℃for6hdemonstratesaslightlylowerhardness(i.e.,11.521GPa),whichisstillhigherthanthesamplesinteredat1450℃.Intermsofelasticmodulus,thesamplesinteredbytraditionalmethodat1600℃for6hdisplaysthemaximumelasticmodulus(i.e.,194.68GPa),slightlysurpassingthatofthesamplesinteredbymicrowavemethodat1500℃.AccordingtotheEvansandNiiharaempiricalformulas,thesamplesinteredbytraditionalmethodat1600℃exhibitsafracturetoughnessof0.280MPa·m1/2and0.305MPa·m1/2,respectively.Also,thesamplesinteredbymicrowavemethodat1500℃hasafracturetoughnessof0.359MPa·m1/2and0.347MPa·m1/2,respectively.ConclusionsThedensityoftheBZCYelectrolytewith5%(inmass)NiOsinteringaidssinteredbymicrowavemethodat1500℃for40minwascomparabletothatofthesamplesinteredbytraditionalmethodat1600℃for6h,achievingadensityofover96%.Thegrainsizeobtainedbymicrowavesinteringwassmaller.Theimpedanceandconductivityofthesampleproducedbymicrowavesinteringexhibitedminimaldifferences,comparedtothoseobtainedbytraditionalsintering.Thegrainimpedanceat650℃measuredwas34.81Ω·cm2,andtheconductivitywas6.41×10-4S·cm-1.Thegrainboundaryimpedanceofmicrowave-sinteredsampledecreasedastheoperatingtemperatureincreased.Thisdecreasecouldbeattributedtothesmallergrainsizeachievedbymicrowavesinteringsinceasmallergrainsizeresultedinagreaternumberofgrainboundaries,therebyincreasingtheimpactonthegrainboundaryimpedance.Furthermore,theactivationenergyforconductivityinmicrowave-sinteredsampleswasonly1.071eV.Theaveragehardnessofthesamplessinteredbymicrowavesinteringat1500℃for40minreached12.379GPa,whichwashigherthanthatobtainedbyconventionalsinteringat1600℃for6h.Theaverageelasticmodulusofthemicrowave-sinteredsamplereached190.8GPa,whichwassimilartothatoftraditionalsinteredsamples.AccordingtothestatisticsofindentationandcracklengthinSEMimages,thecracktypewasradialcrack.BasedontheEvansandNiiharaformulas,theresultsofmicrowave-sinteredsampleswere0.359MPa·m1/2and0.347MPa·m1/2respectively,whichwerehigherthanthoseofconventionally-sinteredsamples.
作者：秦嘉辰 高燕 焦震钧 张进 严资林Author：QINJiachen GAOYan JIAOZhenjun ZHANGJin YANZilin
作者单位：哈尔滨工业大学(深圳)理学院,广东深圳518055
刊名：硅酸盐学报 ISTICEIPKU
Journal：JournaloftheChineseCeramicSociety
年，卷(期)：2024, 52(7)
分类号：TM911.4
关键词：固体氧化物燃料电池 质子导体电解质 微波烧结 电化学性能 力学性能
Keywords：solidoxidefuelcells proton-conductingelectrolyte microwavesintering electrochemicalperformance mechanicalproperties
机标分类号：TM911.4TQ174TM205.1
在线出版日期：2024年7月24日
基金项目：国家自然科学基金，深圳市自然科学基金，广东省珠江人才计划，广东省基础与应用基础研究基金质子导体电解质钇掺杂锆酸铈钡微波烧结制备及其电化学和力学性能[
期刊论文] 硅酸盐学报--2024, 52(7)秦嘉辰 高燕 焦震钧 张进 严资林质子陶瓷燃料电池(PCFC)是新一代固体氧化物燃料电池(SOFC)技术的重要发展方向.钇掺杂锆酸铈钡BaZr1-x-yCexYyO3-δ(BZCY)是常用的质子导体电解质材料.然而,BZCY电解质致密化通常需要在超过1700℃的高温烧结5h以上,这不...参考文献和引证文献
参考文献
引证文献
本文读者也读过
相似文献
相关博文
质子导体电解质钇掺杂锆酸铈钡微波烧结制备及其电化学和力学性能 Microwave Sintering of Proton-Conducting Electrolyte Yttrium-Doped Barium Cerium Zirconate and Its Electrochemical and Mechanical Properties
质子导体电解质钇掺杂锆酸铈钡微波烧结制备及其电化学和力学性能.pdf
- 文件大小:
- 22.47 MB
- 下载次数:
- 60
-
高速下载
|
|
