77范文网 - 专业文章范例文档资料分享平台

TiO 2纳米颗粒的制备_光催化性能及羟基自由基研究_县涛(2)

来源:网络收集 时间:2019-04-15 下载这篇文档 手机版
说明:文章内容仅供预览,部分内容可能不全,需要完整文档或者需要复制内容,请下载word后使用。下载word有问题请添加微信号:或QQ: 处理(尽可能给您提供完整文档),感谢您的支持与谅解。点击这里给我发消息

·116·

纳米技术与精密工程第11卷第2期

以500℃下煅烧制备的TiO2样品为催化剂,考察了pH值对COU反应液荧光强度的影响,结果如图9所示,其中,COU质量浓度为1.0×10-3mol/L,催化剂用量为1g/L,紫外光照射时间为1h.可以看出,在酸性条件下,随着溶液pH值的减小,反应液的荧光强度逐渐增强,表明产生的·OH逐渐增多.这是由于随着pH值的减小,TiO2的导带和价带电位呈下降趋势,价带电位降低使得空穴氧化H2O/OH-产生·OH的能力增强,从而导致·OH产量的增加.此外实验发现,在碱性环境中,COU的性质开始发生变化,因此难以通过COU与·

果表明随着煅烧温度的升高,TiO2颗粒逐渐从锐钛相转变为金红石相,带隙从3.21eV减小为3.04eV,颗粒逐渐增大、主要以类球形为主.光催化实验表明,随着煅烧温度的升高,样品的光催化活性呈现出先增大后减小的趋势,500℃下煅烧制备的样品光催化性能最好;随着催化剂用量的增加,光催化效率呈先增大后减小的趋势,最佳催化剂用量为4.0g/L;在pH值不太高时(≤7.2),光催化效率随pH值的升高呈下降趋势.·OH检测表明,其产率随样品煅烧温度、催化剂用量及pH值的变化规律与光催化效率的变化规律基本一致,表明·OH可能是光催化降解有机染料的主要活性物种.参考文献:

OH的反应来准确检测反应溶液中·OH的信息.

250200荧光强度150100500350

400

450500

波长/nm

pH=1.5pH=3.7pH=6.1

[1]MillsA,DaviesRH,WorsleyD.Water-purificationbysemiconductorphotocatalysis[J].ChemicalSocietyReviews,1993,22(6):417-425.

[2]

550

600

HoffmannMR,MartinST,ChoiW,etal.Environmentalapplicationsofsemiconductorphotocatalysis[J].ChemicalReviews,1995,95(1):69-96.

图9不同pH值条件下COU反应液的荧光强度

Fig.9PLintensitiesofCOUreactionsolutionsatdifferentpHvalues

[3]CareyJH.PhotodechlorinationofPCB’sinthepresenceoftitaniumdioxideinaqueoussuspensions[J].BulletinofEn-vironmentalContaminationandToxicology,1976,16(6):697-701.

以500℃下煅烧制备的TiO2样品为催化剂,考察催化剂加载量对COU反应液荧光强度的影响,其中,

[4]BahnemanntDW,KholuiskayaSN,DillertR,etal.Pho-todestructionofdichloroaceticacidcatalyzedbynano-sizedTiO2particles[J].AppliedCatalysisB:Environmental,2002,36(2):161-169.

COU质量浓度为1.0×10-3mol/L,溶液pH=6.1(自然pH

值),紫外光照射时间为1h.结果如图10所示,随着催化剂用量的增加,反应液的荧光强度呈先增大后减小的趋势,催化剂用量为4.0g/L时最强.这种变化规律与TiO2样品光催化降解MO的规律一致,进一步表明·OH可能是TiO2光催化降解MO的主要活性物种.

360300荧光强度[5]RuanSP,WuFQ,ZhangT,etal.SurfacestatestudiesofTiO2nanoparticlesandphotocatalyticdegradationofmethylorangeinaqueousTiO2dispersions[J].MaterialsChemistryandPhysics,2001,69(1/2/3):7-9.

[6]IshibashiK,FujishimaA,WatanabeT,etal.DetectionofactiveoxidativespeciesinTiO2photocatalysisusingthefluorescencetechnique[J].ElectrochemistryCommunica-tions,2000,2(3):207-210.

240180120600

350

400

450

4.02.51.05.57.0g/Lg/Lg/Lg/Lg/L

[7]IshibashiK,FujishimaA,WatanabeT,etal.QuantumyieldsofactiveoxidativespeciesformedonTiO2photocata-lyst[J].JournalofPhotochemistryandPhotobiologyA,2000,134(1/2):139-142.

500波长/nm

550600

[8]LouitG,FoleyS,CabillacJ,etal.ThereactionofcoumarinwiththeOHradicalrevisited:Hydroxylationpro-ductionproductanalysisdeterminedbyfluorescenceandchromatography[J].RadiationandPhysicsandChemistry,2005,72(2/3):119-124.

图10不同催化剂用量下COU反应液的荧光强度

Fig.10PLintensitiesofCOUreactionsolutionswith

differentphotocatalystloadings

3结语

[9]NewtonaGL,MilliganJR.Fluorescencedetectionofhy-droxylradicals[J].RadiationandPhysicsandChemistry,2006,75(4):473-478.

采用聚丙烯酰胺凝胶法制备了TiO2纳米颗粒,结

2013年3月县涛等:TiO2纳米颗粒的制备、光催化性能及羟基自由基研究

·117·

[10]BottleSE,HansonGR,MicallefAS.ApplicationoftheNanotechnologyandPrecisionEngineering,2011,9(4):322-328(inChinese).

[19]LiuZ,JinJ,ChenS,etal.Effectofcrystalformandpar-

newEPRspintrap1,1,3-trimethylisoindolen-oxide

(TMINO)intrappingHO·andrelatedbiologicallyimpor-

tantradicals[J].OrganicBiomolecularChemistry,2003,1:2585-2589.

[11]熊道文,司马小峰,朱文涛,等.纳米TiO2及ZnO悬浮液

中·OH的生成[J].环境化学,2010,29(5):825-829.

ticlesizeoftitaniumdioxideonthephotodegradationbe-haviourofethylene-vinylacetatecopolymer/lowdensitypolyethylenecomposite[J].PolymerDegradationandSta-bility,2011,96(1):43-50.

[20]AkpanUG,HameedBH.Parametersaffectingthephoto-

XiongDaowen,SimaXiaofeng,ZhuWentao,etal.Gener-ationofhydroxylradicalsinnanoscaleTiO2andZnOsus-pensions[J].EnvironmentalChemistry,2010,29(5):825-829(inChinese).

[12]RobabM,BakhshaliM,MohammadR.Photocatalyticde-

catalyticdegradationofdyesusingTiO2-basedphotocata-lysts:Areview[J].JournalofHazardousMaterials,2009,170(2/3):520-529.

[21]县

涛,杨

华,沈

希,等.聚丙烯酰胺凝胶法合成

compositionofamoxicillintrihydrateantibioticinaqueoussolutionsunderUVirradiationusingSn/TiO2nanoparticles

[J].InternationalJournalofPhotoenergy,2012,2012:1-

BiFeO3纳米颗粒[J].无机材料学报,2010,25(3):251-253.XianTao,YangHua,ShenXi,etal.SynthesisofBiFeO3nanoparticlesbyapolyacrylamidegelroute[J].JournalofInorganicMaterials,2010,25(3):251-253(inChinese).

[22]GuillaumeL,SarahF,JulieC,etal.Thereactionof

11.

[13]XiangQ,YuJ,WongPK.Quantitativecharacterizationof

hydroxylradicalsproducedbyvariousphotocatalysts[J].JournalofColloidandInterfaceScience,2011,357(1):163-167.

[14]CziliH,HorvathA.Applicabilityofcoumarinfordetection

coumarinwiththeOHradicalrevisited:Hydroxylationproductanalysisdeterminedbyfluorescenceandchro-matography[J].RadiationPhysicsandChemistry,2005,72(2/3):119-124.

[23]SpurrRA,MyersH.Quantitativeanalysisofanataserutile

andmeasuringhydroxylradicalsgenerationbyphototexci-tationofTiO2nanoparticles[J].AppliedCatalysisB:Envi-ronmental,2008,81(3/4):295-302.

[15]Abdulla-Al-MamunM,KusumotoY,ZannatT,etal.Syn-

mixtureswithanX-raydiffractometer[J].AnalyticalChem-istry,1957,29(5):760-762.

[24]KomornickoiS,RadeckaM,SobasP.Structural,electrical

ergisticcell-killingbyphotocatalyticandplasmonicpho-tothermaleffectsofAg@TiO2core-shellcompositenan-oclustersagainsthumanepithelialcarcinoma(HeLa)cells

[J].AppliedCatalysisA:General,2011,398(1/2):134-

andopticalpropertiesofTiO2-WO3polycrystallineceramics

[J].MaterialsResearchBulletin,2004,39(13):2007-

2017.

[25]ShenL,BaoN,ZhengY,etal.Hydrothermalsplittingof

142.

[16]张

雯,王绪绪,林华香,等.磁场对光催化反应羟基自由基生成速率的影响[J].化学学报,2005,63(18):1765-

titanatefiberstosingle-crystallineTiO2nanostructureswithcontrollablecrystallinephase,morphology,microstructure,andphotocatalyticactivity[J].TheJournalofPhysicalChemistryC,2008,112(24):8809-8818.

[26]HurumDC,AgriosAG,GrayKA,etal.Explainingthe

1768.

ZhangWen,WangXuxu,LinHuaxiang,etal.Influenceofmagneticfieldontheformationrateofhydroxylradicalinphotocatalysis[J].ActaChimicaSinica,2005,63(18):1765-1768(inChinese).

[17]张天永,范巧芳,王

正,等.TiO2/海泡石催化剂的光催化

降解性能[J].纳米技术与精密工程,2008,6(1):9-13.

enhancedphotocatalyticactivityofdegussaP25mixed-phaseTiO2usingEPR[J].TheJournalofPhysicalChem-istryB,2003,107(19):4545-4549.

[27]ChenD,RayAK.Removaloftoxicmetalionsfrom

wastewaterbysemiconductorphotocatalysis[J].ChemicalEngineeringScience,2001,56(4):1561-1570.

[28]IoannisKK,TriantafyllosAA.TiO2-assistedphotocatalytic

ZhangTianyong,FanQiaofang,WangZheng,etal.Pho-tocatalyticdegradationactivityofTiO2/sepiolitecatalyst[J].NanotechnologyandPrecisionEngineering,2008,6(1):9-13(inChinese).

[18]杨

朔,尹荔松,阳素玉,等.TiO2/ZnO纳米管的制备及其光催化性能[J].纳米技术与精密工程,2011,9(4):322-

degradationofazodyesinaqueoussolution:kineticandmechanisticinvestigations:Areview[J].AppliedCatalysisB:Environmental,2004,49(1):1-14.

[29]SunB,VorontsovAV,PanagiotisG,etal.Roleofplat-

328.

YangShuo,YinLisong,YangSuyu,etal.PreparationofTiO2/ZnOnanotubesandtheirphotocatalyticactivity[J].

inumdepositedonTiO2inphenolphotocatalyticoxidation

[J].Langmuir,2003,19(8):3151-3156.

(责任编辑:孙媛媛)

百度搜索“77cn”或“免费范文网”即可找到本站免费阅读全部范文。收藏本站方便下次阅读,免费范文网,提供经典小说综合文库TiO 2纳米颗粒的制备_光催化性能及羟基自由基研究_县涛(2)在线全文阅读。

TiO 2纳米颗粒的制备_光催化性能及羟基自由基研究_县涛(2).doc 将本文的Word文档下载到电脑,方便复制、编辑、收藏和打印 下载失败或者文档不完整,请联系客服人员解决!
本文链接:https://www.77cn.com.cn/wenku/zonghe/599051.html(转载请注明文章来源)
Copyright © 2008-2022 免费范文网 版权所有
声明 :本网站尊重并保护知识产权,根据《信息网络传播权保护条例》,如果我们转载的作品侵犯了您的权利,请在一个月内通知我们,我们会及时删除。
客服QQ: 邮箱:tiandhx2@hotmail.com
苏ICP备16052595号-18
× 注册会员免费下载(下载后可以自由复制和排版)
注册会员下载
全站内容免费自由复制
注册会员下载
全站内容免费自由复制
注:下载文档有可能“只有目录或者内容不全”等情况,请下载之前注意辨别,如果您已付费且无法下载或内容有问题,请联系我们协助你处理。
微信: QQ: