?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.relation=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F31361%2F&rft.title=THE+EFFECT+OF+MONOMER+SEQUENCE+ON+THE+PROPERTIES+AND+DEVICE+PERFORMANCE+OF+CONJUGATED+ORGANIC+SEMICONDUCTORS&rft.creator=Zhang%2C+Shaopeng&rft.description=Although+sequence+effect+can+potentially+be+a+powerful+tool+to+tune+the+photophysical+properties+of+conjugated+oligomers+and+copolymers+prepared+from+donor+and+acceptor+monomers%2C+nearly+all+research+to+date+focuses+on+the+alternating+structure.++Little+is+known+about+the+properties+of+other+sequences+and+sequence+has+not+been+exploited+as+a+tool+for+tuning+these+materials+for+specific+applications.+In+order+to+explore+this+potentially+powerful+tool%2C+a+series+of+sequenced+phenylene-vinylene+oligomers+was+synthesized+and+investigated+both+experimentally+and+computationally.+Using+Horner-Wadsworth-Emmons+(HWE)+chemistry%2C+dimers%2C+trimers%2C+tetramers%2C+pentamers%2C+and+hexamers+were+prepared+from+two+building+block+monomers%2C+a+relatively+electron-poor+unsubstituted+p-phenylene-vinylene+and+an+electron-rich+dialkoxy-substituted+p-phenylene-vinylene.+UV-Vis+absorption%2Femission+spectra+and+cyclic+voltammetry+demonstrated+that+the+optoelectronic+properties+of+these+oligomers+depended+significantly+on+sequence.+%0D%0ATo+further+understand+the+influence+of+monomer+sequence+on+the+properties+and+solar+cell+performance+of+donor-acceptor+conjugated+oligomers%2C+a+library+of+dimers%2C+trimers%2C+and+tetramers+were+prepared+from+phenylene+and+benzothiadiazole+monomers+linked+by+vinylene+groups.+Optical+and+electrochemical+studies+established+the+influence+of+sequence+on+both+the+%EF%81%ACmax+and+redox+potentials+of+this+series+of+structurally+related+oligomers.+The+effect+of+end+groups+(cyano%2C+bromo%2C+and+alkyl)+was+also+demonstrated+to+be+important+for+the+properties+of+these+oligomers.+Bulk+heterojunction+(BHJ)+solar+cells+fabricated+with+selected+tetramers+as+the+donor+exhibited+power+conversion+efficiencies+that+varied+by+a+factor+of+three+as+a+function+of+sequence.+%0D%0AThe+sequence+effect+on+donor-acceptor+conjugated+polymers+was+also+studied.+Two+trimeric+isomers%2C+comprising+dialkoxy+phenylene+vinylene%2C+benzothiadiazole+vinylene%2C+and+alkyl+endgroups+with+terminal+olefins%2C+were+synthesized.+Sequence+effects+were+evident+in+the+optical%2Felectrochemical+properties+and+thermal+properties.+The+trimers+were+used+as+macromonomers+in+an+ADMET+polymerization+to+give+sequenced+polymers.++The+optical+and+electrochemical+properties+were+similar+to+those+of+their+trimer+precursors%E2%80%94sequence+effects+were+still+evident.++%0D%0AThese+results+suggest+that+sequence+control+is+important+for+tuning+optoelectronic+properties+and+photovoltaic+performance+of+these+structurally+related+conjugated+oligomers.+The+polymerization+of+oligomeric+sequences+is+a+practical+approach+for+the+incorporation+of+sequence+into+polymers.&rft.date=2017-07-02&rft.type=University+of+Pittsburgh+ETD&rft.type=PeerReviewed&rft.format=application%2Fpdf&rft.language=en&rft.identifier=http%3A%2F%2Fd-scholarship-dev.library.pitt.edu%2F31361%2F1%2FShaopeng%2520dissertation%25204-19-17.pdf&rft.identifier=++Zhang%2C+Shaopeng++(2017)+THE+EFFECT+OF+MONOMER+SEQUENCE+ON+THE+PROPERTIES+AND+DEVICE+PERFORMANCE+OF+CONJUGATED+ORGANIC+SEMICONDUCTORS.++Doctoral+Dissertation%2C+University+of+Pittsburgh.++++(Unpublished)++