A review of solar and visible light active TiO2 photocatalysis for treating bacteria, cyanotoxins and contaminants of emerging concern

摘要

Researchintothedevelopmentofsolarandvisiblelightactivephotocatalystshasbeensignificantlyincreasedudinrecentyearsduetoitswiderangeofapplicationsintreatingcontaminantsofemergingconcern(CECs),udendocrine disruptingcompounds(EDCs), bacteriaandcyanotoxins.SolarphotocatalysisisfoundtobehighlyudeffectiveintreatingawiderangeofCECsfromsourcessuchaspharmaceuticals,steroids,antibiotics,phthalates,uddisinfectants,pesticides,fragrances(musk),preservativesandadditives.Similarly,anumberofEDCsincludingudpolycyclicaromatichydrocarbons(PAHs),alkylphenols(APs),bisphenolA(BPA),organotins(OTs),volatileor-udganic compounds(VOCs),naturalandsyntheticestrogenicandandrogenicchemicals,pesticides,andheavyudmetalscanberemovedfromcontaminatedwaterbyusingsolarphotocatalysis.Photocatalysiswasalsofoundudeffectiveintreatingawiderangeofbacteriasuchas Staphylococcusaureus,Bacillussubtilis,Escherichiacoli,udSalmonellatyphi and Micrococcuslylae. ThecurrentreviewalsocomparestheeffectivenessofvariousvisibleudlightactivatedTiO2 photocatalystsfortreatingthesepollutants. Dopingorco-dopingofTiO2 usingnitrogen,udnitrogen–silver,sulphur,carbon,copperandalsoincorporation ofgraphenenano-sheetsarediscussed.Theuseudof immobilisedTiO2 for improvingthephotocatalyticactivityisalso presented.Decoratingtitaniaphotocatalystudwithgrapheneoxide(GO)isofparticularinterestduetoGO'sabilitytoincreasethephotocatalyticactivityofudTiO2. TheuseGOtoincreasethephotocatalyticactivityofTiO2 againstmicrocystin-LR(MC-LR)underUV-Aandudsolarirciationisdiscussed.TheenhancedphotocatalyticactivityofGO–TiO2 comparedtothecontrolmaterialisudattributedtotheeffectiveinhibitionoftheelectron–holerecombinationbycontrollingtheinterfacialchargeudtransferprocess.Itisconcludedthatthereisacriticalneedforfurtherimprovementoftheefficiencyoftheseudmaterialsiftheyaretobeconsideredforbulkindustrialuse.