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SpringerThesesRecognizingOutstandingPh.D.ResearchMetalloenzymesasInspirationalElectrocatalystsforArtificialPhotosynthesisAndreasS.J.L.BachmeierFromMechanismtoModelDevicesSpringerThesesRecognizingOutstandingPh.D.ResearchAimsandScopeTheseries“SpringerTheses”bringstogetheraselectionoftheverybestPh.D.thesesfromaroundtheworldandacrossthephysicalsciences.Nominatedandendorsedbytworecognizedspecialists,eachpublishedvolumehasbeenselectedforitsscientificexcellenceandthehighimpactofitscontentsforthepertinentfieldofresearch.Forgreateraccessibilitytonon-specialists,thepublishedversionsincludeanextendedintroduction,aswellasaforewordbythestudent’ssupervisorexplainingthespecialrelevanceoftheworkforthefield.Asawhole,theserieswillprovideavaluableresourcebothfornewcomerstotheresearchfieldsdescribed,andforotherscientistsseekingdetailedbackgroundinformationonspecialquestions.Finally,itprovidesanaccrediteddocumentationofthevaluablecontributionsmadebytoday’syoungergenerationofscientists.Thesesareacceptedintotheseriesbyinvitednominationonlyandmustfulfillallofthefollowingcriteria�TheymustbewritteningoodEnglish.�ThetopicshouldfallwithintheconfinesofChemistry,Physics,EarthSciences,EngineeringandrelatedinterdisciplinaryfieldssuchasMaterials,Nanoscience,ChemicalEngineering,ComplexSystemsandBiophysics.�Theworkreportedinthethesismustrepresentasignificantscientificadvance.�Ifthethesisincludespreviouslypublishedmaterial,permissiontoreproducethismustbegainedfromtherespectivecopyrightholder.�Theymusthavebeenexaminedandpassedduringthe12monthspriortonomination.�Eachthesisshouldincludeaforewordbythesupervisoroutliningthesignifi-canceofitscontent.�Thethesesshouldhaveaclearlydefinedstructureincludinganintroductionaccessibletoscientistsnotexpertinthatparticularfield.MoreinformationaboutthisseriesatficialPhotosynthesisFromMechanismtoModelDevicesDoctoralThesisacceptedbyUniversityofOxford,UK123AuthorDr.AndreasS.J.L.BachmeierBusinessUnitCatalystsClariantMunichGermanySupervisorProf.FraserA.ArmstrongDepartmentofChemistryUniversityofOxfordOxfordUKISSN2190-5053ISSN2190-5061(electronic)SpringerThesesISBN978-3-319-47068-9ISBN978-3-319-47069-6(eBook)DOI10.1007/978-3-319-47069-6LibraryofCongressControlNumber:2016953207©SpringerInternationalPublishingAG2017Thisworkissubjecttocopyright.AllrightsarereservedbythePublisher,whetherthewholeorpartofthematerialisconcerned,specificallytherightsoftranslation,reprinting,reuseofillustrations,recitation,broadcasting,reproductiononmicrofilmsorinanyotherphysicalway,andtransmissionorinformationstorageandretrieval,electronicadaptation,computersoftware,orbysimilarordissimilarmethodologynowknownorhereafterdeveloped.Theuseofgeneraldescriptivenames,registerednames,trademarks,servicemarks,etc.inthispublicationdoesnotimply,evenintheabsenceofaspecificstatement,thatsuchnamesareexemptfromtherelevantprotectivelawsandregulationsandthereforefreeforgeneraluse.Thepublisher,theauthorsandtheeditorsaresafetoassumethattheadviceandinformationinthisbookarebelievedtobetrueandaccurateatthedateofpublication.Neitherthepublishernortheauthorsortheeditorsgiveawarranty,expressorimplied,withrespecttothematerialcontainedhereinorforanyerrorsoromissionsthatmayhavebeenmade.Printedonacid-freepaperThisSpringerimprintispublishedbySpringerNatureTheregisteredcompanyisSpringerInternationalPublishingAGTheregisteredcompanyaddressis:Gewerbestrasse11,6330Cham,SwitzerlandSupervisor’sForewordArtificialphotosynthesis(AP)researchinvolvesdesigningandbuildingphysicalsystemsthatmimicnaturalphotosynthesisbyusingsolarenergytoconvertwaterintohydrogenandoxygen,leadingalsototheendothermicconversionofcarbondioxideintoorganicmolecules.IfAPcouldbemadeefficientandscalable,itwouldofferawayofstoringsolarenergyaschemicalbondsina‘fuel’.Althoughitiswellknownthatelectricitygeneratedbyphotovoltaiccellscanbeusedtoelectrolysewater,itmightadvantageoustocombinethesetwostepsinasingledevice.EarlyresearchonAPfocusedonsinglematerialsthatsplitwaterwhenilluminated,butlaterresearchhastriedtomimicmorecloselythemodularprocessesthatoccurinchloroplasts.Hence,photosynthesisneedsaminimumofthreecomponentsboltedtogether:(1)theexci-tationcentre(chlorophyllinnaturalphotosynthesis/semiconductorinAP)convertstheenergyofphotonsintoaseparatedelectronandhole;(2)thefuel-formingelec-trocatalyst(hydrogenaseorferredoxinNADP+reductaseinnaturalphotosynthesis)usesexcitedelectronstosplitwaterandproducehydrogenororganicmolecules;(3)thehole-quenchingelectrocatalystconvertswaterintooxygen(theoxygen-evolvingMnCaOclusterinnaturalphotosynthesis)releaseselectronsthatarerequiredtofillthevacancies(‘holes’)leftinthevalenceorbitals(orband)whenelectronsareexcited,thuscompletingacycle.Inworkleadingupto2012,priortoAndreasBachmeierstartinginOxfordasaGraduateScholaratStJohn’sCollege,mygrouphaddrawnattentiontoobser-vationswehadmaderegardingthesuperbefficiencyofenzymesaselectrocatalystswhenattachedtosuitableelectrodematerials.Hence,theideabehindattachingen