KF熔盐中钾插入石墨层间的电化学研究(英文)

KF熔盐中钾插入石墨层间的电化学研究(英文)Electrochemical Study on Potassium Insertion into Graphite Intercalation in KF

KF() 熔盐中钾插入石墨层间的电化学研究英文 ElectrochemicalStudyonPotassiumInsertionintoGraphite IntercalationinKFMoltenSalt Introduction Theuseofmoltensaltsaselectrolytesinelectrochemical systemshasbeenasubjectofresearchforseveraldecades.One particularareaofinterestisthestudyoftheinsertionofalkaliand alkalineearthmetalsintographiteintercalationcompounds (GICs).Thesematerialshavealayeredstructureconsistingof graphitelayersseparatedbyintercalationsites.Theinsertionof metalionsintothesesitescanmodifytheelectronicandphysical propertiesoftheGICs,makingthemattractiveforawiderangeof applications,includingenergystorageandconversiondevices.In thisstudy,wefocusontheelectrochemicalbehaviorofpotassium ionsinamoltenKFelectrolyteandtheirinsertionintographite intercalationcompounds. ExperimentalMethodology Theelectrochemicalexperimentswerecarriedoutina three-electrodesetupcomposedofagraphiteworkingelectrode, aplatinumcounterelectrode,andasilver/silverchloridereference electrode.Theelectrolyteconsistedofa45:55(wt%)mixtureofKF andKClmoltensaltwithameltingpointof880°C.Thegraphite intercalationcompoundusedwasnaturalgraphiteflakesthat weretreatedwithnitricacidtoexpandtheinterlayerspacing.The specificsurfaceareaofthegraphitewasdeterminedby Brunauer-Emmett-Teller(BET)analysisusingnitrogenadsorption isotherms.Structuralandmorphologicalcharacteristicsofnatural graphiteandexpandedgraphitewerecharacterizedbyX-ray diffraction(XRD)andscanningelectronmicroscopy(SEM), respectively. ResultsandDiscussion Thecyclicvoltammetry(CV)resultsobtainedforthe potassiuminsertioninmoltenKFelectrolyteusingnatural graphiteandexpandedgraphiteasworkingelectrodesrevealed distinctdifferencesinthevoltammograms.TheCVcurvesfor naturalgraphiteexhibitedthreemainredoxpeaks,corresponding totheK+/K,K/K2,andK2/K3redoxcouples,asshowninFigure1.