SnO2基 R134a气体传感器ppt

SnO2-basedR134agassensor－Sensingmaterials

preparation,gasresponseandsensingmechanism

（SnO2基R134a气体传感器：传感材料的制备，

气体响应和传感机理）成员：李月飞201213316

郭建军201213325作者介绍：陈俊琛，2008年获得上海大学应用化学专业学士学位。此后，她继续攻读上海大学无机化学理科硕士学位。目前，她主要研究方向是合成以SnO2和Al2O3材料的介孔结构以及其在气体传感器中的应用。徐甲强，1988年毕业于中国科技大学材料科学系，并获理学硕士学位。2005年获得上海大学材料科学博士学位。他研究方向包括气体传感器，纳米材料的合成和应用。Contents：AbstractIntroductionExperimentalResultsanddiscussionConclusionsContents：AbstractIntroductionExperimentalResultsanddiscussionConclusions

Abstract：

◆TheexperimentalresultsindicatedthattheresponsetowardsR134a

oftheSnO2-based

gassensorcanbesignificantlyenhancedbyloadingnoblemetalandusingcatalyticcoating.◆ThesensorbasedonadoublelayerfilmSnO2(Au)/Al2O3(Au)showedsatisfactoryresultsincludinglargeresponse,goodselectivity,highlong-termstability,fastresponseandrecovery,revealingitspotentialapplicationinthedetectionofrefrigerantsandthemaintenanceofairconditionsystems.（基于双层薄膜SnO2（Au）/zAl2O3（Au）的传感器展示出令人满意的结果，，，显示出其在制冷剂检测及空调系统维护方面有应用潜力。）

补充：

气体传感器定义：能够采集气体的某些信息（如：浓度、种类）并把采集到的信息转化为人们更易识别的信号（如电信号、声信号、光信号、数字信号等）,凡是具有这种功能的部件或装置，就是气体传感器。Contents：AbstractIntroductionExperimentalResultsanddiscussionConclusions

Introduction：

WedisclosethatSnO2sensorsdecoratedbyAu-,Ag-,Pt-loadingandAl2O3catalystcoatingwereusedtoimprovetheresponsetoR134a.TheresultsindicatethatthenewtypeofgassensortowardsR134awithlargeresponse,goodselectivity,highlong-termstability,fastresponseandrecoverycanbeobtained.（结果表明，新型气体传感器对R134a的响应大，选择性好，长期稳定性高，响应快和可恢复。）Contents：AbstractIntroductionExperimentalResultsanddiscussionConclusions

Experimental：

Fig.1.Sketchofthegassensorstructure.Contents：AbstractIntroductionExperimentalResultsanddiscussionConclusions

Structureandmorphology：

Fig.2.TEMimagesofSnO2.

Structureandmorphology：

Fig.3.TEMimagesofporousAl2O3.

Structureandmorphology：

Fig.4.SEMimagesofSnO2.

Speculateone：

●Basedontheseobservations，wespeculatethatmesoscopicporesmayprovidemoregaschannelsandimprovetheefficiencyintransportationofgases,whichisafavourablefeatureforgassensing.（基于这些观察，我们推测，介观孔可以提供更多的气体通道提高运输气体的效率，这是气体传感一个有利的特征。）

Structureandmorphology：

Fig.5.Nitrogenadsorptionisothermsandcorrespondingporesizedistribution(inset)oftheporousAl2O3annealedat500◦C.

Speculatetwo：

●WespeculatethatitisduetotheproperporesizecanR134afragmentsreachtheSnO2layerthroughtheporousAl2O3layer.（我们猜想正是由于有适当的孔径，R134a碎片才能通过多孔氧化铝层到达到SnO2层.）

Gas-sensingproperties：

Fig.6.Theresponseto100ppmR134aofSnO2withandwithoutCl−atdifferentpHandtheresponsesto100ppmR134aoffourkindsofsensorsatdifferentworkingtemperature(inset).

Conclusionone：

★WeobservedthatSnO2withoutcontainingCl−hadhigherresponsethanthatofSnO2containingCl−;bothofthetwoseriesofSnO2obtainedatpH=3hadthelargestresponse.Conclusiontwo：

★TheresultssuggestthatSnO2(Au)/Al2O3(Au)hastheoveralllargestresponse;itsresponsevaluetowardsR134aat100ppmreachesashighas8.7.（结果表明,SnO2(Au)/Al2O3(Au)整体响应最大;在100ppm时，对R134a的响应值高达8.7。）

Theresultsrevealthatthegassensorsallreachtheirhighestresponseat350◦C,sowechoose350◦Casanoptimalworkingtemperature.

（350◦C最佳响应温度。）Gas-sensingproperties：Fig.8.StabilityofSnO2(Au)/Al2O3(Au)to100ppmR134a.Conclusion：◆ThestableresponsevalueindicatesthatthesensorbasedonSnO2(Au)/Al2O3(Au)exhibitshighlong-termstability.（这些稳定的响应值表明,基于SnO2(Au)/Al2O3(Au)的传感器具有长期稳定性高的特性。）Gas-sensingproperties：Fig.9.ResponseofSnO2(Au)/Al2O3(Au)todifferentgasesat100ppm.Conclusion：◆Wegettheconclusionthatthesensorshaveafairselectivity,butsomeissueswithseveralinterferences(ethanol,acetoneandsoon)stillexist.（公平选择性，存在干扰因素如乙醇，丙酮等）Gas-sensingproperties：■Tosumup,thesensorbasedondoublelayerfilmofSnO2(Au)/Al2O3(Au)showssatisfactorysensingpropertiesforR134adetection.IthaspromisingprospectinmonitoringtheleakageandconcentrationoftheR134aescapedduringtheproductionandapplicationofrefrigerants.（总之,SnO2(Au)/Al2O3(Au)传感器对R134a检测显示了满意的传感性能。其在制冷剂检测及空调系统维护方面有应用潜力。）Gas-sensingmechanismofR134a：Fig.10.FT-IRspectraofSnO2beforeandaftercalcinatingat350◦CinR134a.（横：波数：纵：透射度）Speculate:★TheFT-IRspectrumshowninFig.10displaysnosignificantdifferencebeforeandaftercalcinatingtheSnO2at350◦CunderR134a,becausethatthepeakdisplayedintherangeof4000–3500cm−1belongstoH2O,andthepeakintherangeof1000–500cm−1isthebondofSn–O.（没明显差异，峰值范围）Gas-sensingmechanismofR134a：Fig.11.FT-IRspectraofAl2O3beforeandaftercalcinatingat350◦CinR134a.Speculate:★TheFT-IRspectrumshowninFig.11demonstratesanobviouschangeintherangeof500–1000cm−1beforeandaftercalcinatingtheAl2O3at350◦CunderR134a.Thischangema