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2015PPGUndergraduateResearchFellowshipProgram

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Synthesis and Characterization of Block Copolymers for Organic PhotovoltaicsBryan Smith1, Melissa Aplan1, Dr. Youngmin Lee1,2, and Dr. Enrique Gomez1,2

1Department of Chemical Engineering, Pennsylvania State University; 2Material Science Institute, Pennsylvania State University

The PPG Undergraduate Research Fellowship Program is supported by the PPG Research Foundation through the Materials Research Institute

Introduction Target Copolymers

Donor End Group ControlReactions

Results & CharacterizationWorkingtowards…• Higherefficiency• Greaterunderstanding• Newmaterials• Cheaperproduction• Flexibility

Whyblockcopolymer?• Higherperformanceall

polymeractivelayer• Morphologycontrol• Betterdonor/acceptor

interface• Blockcrystallization

P3HT-b-PCPDTBT

PCPDT-b-PNDIBT

P3HT-b-PNDIT

P3HT-b-PFBT

Factorsweconsider…• Literaturehomopolymerblendperformance• HOMO/LUMOlevels• Bandgap• Rangeofabsorption

Donor Acceptor

SuzukiCoupling

KumadaCoupling

P3HT-b-PFTBTsolarcellswithrecordnear3%efficiencydramaticallyoutperformP3HT-PFTBTblendcells

MALDI-TOFEndGroupAnalysis• Intensitiescorrespondtoendgroupdistribution• Controlcriticalforsynthesispathway• AffectedbyO2,H2O,temperature,Grignardquantity

P3HT-b-PFBTSynthesisScheme

NMRAnalysis• Calculatemoleandmassfractionfrompeakintegration• Limitedbysolubility• PairedwithGPC,UV-Vistoconfirmblockcopolymerization

Summary• RefinedendgroupfunctionalizedP3HT

synthesis

• SynthesizedP3HT-b-PFBT

Future Work• Synthesizeothertargets• Testdeviceswithnewactivelayers• Improveaccuracyandrangeofcharacterization

Suzuki

Kumada

ExampleP3HT-b-PFTBTGPCAnalysis• Indicatespurity• ComparisontohomopolymerP3HTdata

C.Guo,etal.,NanoLett.,2013,13,2957

UV-VisAnalysis• Blockcopolymerspectracloselyresemblessumofhomopolymer

spectra• Spectraofsamethicknessfilmscanbeanalyzedtoreportvolume

fractionuponcreationofhomopolymerstandards

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Time(mins)

P3HTHomopolymer

P3HT-b-PFTBT

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