Inthisstudy,one-dimensionaltitaniananotubes(TNTs)weresynthesizedusingacombinedprocessofchemicalandhydrothermaltreatments,andtheiractivitiesforthephotocatalyticreactionsofselectedgaseouspollutantsatsub-ppmlevelsweredetermined.Additionally,thepropertiesoftheTNTswereexaminedusingselectedspectroscopicmethods.TheannealedTNTsshowedhigherphotocatalyticactivitiesforthefourtargetcompoundsthandidtheunannealedTNTs.Forallthetargetcompoundsexceptbenzene,theeffectoftheannealingtemperatureonthedegradationefficiencywasdifficulttodeterminebecausealldegradationefficiencieswereveryhigh.However,forbenzene,whichdecomposedwithalowefficiency,thedegradationactivitiesoftheTNTsincreasedasthetreatmenttemperaturewasincreasedfrom250to300℃,whiletheydecreasedslightlywhenthetemperaturewasincreasedfrom300to400℃.ThesefindingsconfirmthepresenceofanoptimalannealingtemperatureforthesynthesisofTNTs.Moreover,theaveragedegradationextentsforbenzene,toluene,ethylbenzene,ando-xylenedecreasedfrom92%,96%,99%,and98%to77%,86%,92%,and94%,respectively,astheairstreamflowrateincreasedwithintherangeof1-4L/min.Theaveragedegradationextentsdecreasedfrom12%,75%,87%,and88%to3%,29%,46%,and51%,respectively,astheinputconcentrationincreasedfrom0.4to1.9ppm.Overall,thesefindingssuggestthatone-dimensionalTNTscanbeeffectivelyutilizedforthedegradationofgaseouspollutantsunderoptimaloperationalconditions.
