TiO2納米管陣列的可控生長與結構調制及其原位機理研究.pdf

1、上海交通大學博士后學位論文TiO2納米管陣列的可控生長與結構調制及其原位機理研究姓名：劉洪申請學位級別：博士后專業(yè)：物理學；凝聚態(tài)物理指導教師：沈文忠201103AbstractTheTi02nanotubearrayshaveattractedtremendousattentionsinceitwasreportedbyZwillingeta1in1999Ithasbeenextensivelyappliedinmanyfields，

2、especiallythedye—sensitizedsolarcells(DSSCs)duetoitsbroadbandsemiconductingproperties，highaspectratioandexcellentphotocatalyticpropertyThereforethecontrolledsynthesisoftheTi02tubesanddevelopmentofnewfunctionalstructuresh

3、avebeenimportantdirectionsHoweverdespiteofrichexperimentalresults，amoresystematicinvestigationtowardtherealisticbehaviorofthissystemisstillneeded，andlotsofquestionsstillexiststowardthemechanisticdescriptionsThishasinsome

4、degreelimitedthepurposeofthematerialdevelopmentThisworkhassystematicallyinvestigatedtheelectrochemicalgrowthofZi02tubearraysandgivenasetof3DphasediagramsofmorphologicalevolutionWehaveachievedtheoptimizedgrowthofultralarg

5、e(D600nm)andultrasmall(D～lOnm)tubesandagrowthrateformediumsizedtubesuptoll31xm／hItwasfurtherdiscoveredthatthegrowthofsmall(50—90nm)tubeswithspecificsizecouldbe23timesfasterthanthenormalconditionthroughthenonmonotonouscha

6、ngeofthegrowthrateandsizeunderlowtemperaturesFurthermore，ithasbeendiscoveredthatahigh行equency(10叫Hz)andsmallamplitude(802m)oscillationuniversallyexistintheelectrochemicalgrowthofTi02tubes，together誚msignificantmorphologic

7、alchangeintheporeareaofthetubesWiththeenhancementoftheouterconditions(stirringrateormodulmionamplitudeoftheperiodicalvoltage)，surprisinglytheroughnessoftheporesurfaceistotallyannihilatedinsteadofbeingenhanced，thoughthecu

8、rrentoscillationisstrongerInthemeantime，thegrowthrateofthetubeswasgreatlyincreasedItindicatesakeyenrollmentoftheinteractionbetweenthetransportprocessesoftheionicspeciesandthelocalchemicalreactionsunderinfluenceoftheouter