StudyoftheGellingProcessforthePreparationofTinOxideMaterialsBasedonTinTetrabutoxide

Thegellingprocessinthepreparationoftinoxidematerialsbasedontintetrabutoxideisstudied.Sn(OBun)4modifiedbytwomolesofacetylacetone(AcAc)hasastablesix-memberringstructureandislesssusceptivetowater.InasystemwithalowermolarratioofacetylacetonetoSn(OBun)4([AcAc]/[Sn(OBun)4]<2.0)oralargerportionofwater([H2O]/[Sn(OBun)4]>2.5),colloidalsuspensionorwhiteprecipitationwilltakeplace.AsystemwithmolarratiosofbothacetylacetonetoSn(OBun)4andwatertoSn(OBun)4at2.0istransparentandolivaceoussol.Ascatalysts,hydrofluoric,hydrochloric,hydrobromicandaceticacids,andammoniaallacceleratethehydrolysisandcondensationofSn(OBun)4duringthesol-gelprocess.Lightscatteringmeasurementindicatesthatclustersizedistributioninthesolsystemundergoesgradualbroadeningduringthesol-geltransition.