Synthesis, characterization and photovoltaic properties of benzo[c][1,2,5]oxadiazole based conjugated polymers for organic solar cells

Karakurt, Oğuzhan
In this thesis, six conjugated polymers were synthesized by coupling of 2,1,3- benzoxadiazole derivatives with donor groups via Stille polycondensation reactions. Moreover, the effect of molecular weight for P1 and P2, effect of position of alkyl chain for P5 and effect of π-bridge groups for P6 which are selenophene and thiophene on optical, electrochemical, and photovoltaic properties were investigated. Also, modifications on alkyl chains of P3 and P4 were performed to increase their functionalities via post-polymerization reactions. Electronic and optical band gaps of polymers were found as 1.83/1.81, 1.86/1.76, 2.03/1.74, 2.07/1.74, 1.76/1.72, and 2.10/1.71 respectively for P1, P2, P3, P4, P5, and P6. Furthermore, the effect of the addition of gold nanoparticles to the active layer of organic solar cells on photovoltaic properties was analyzed. Synthesized polymers were characterized by infrared (IR) spectroscopy, gel permeation chromatography (GPC), thermal gravimetric analysis (TGA), differential scanning calorimeter (DSC) and UV-Vis- NIR spectroscopy. Redox behaviors and electronic band gaps of polymers were investigated by the cyclic voltammetry (CV) method. Device production and current/voltage property measurements were carried out in a nitrogen-filled glovebox system. While PC71BM was the acceptor unit, synthesized polymers were donor units for the conventional type device structure of ITO/PEDOT:PSS/polymer:PC71BM/LiF/Al. Photovoltaic properties of constructed devices were measured under 100 mW cm-2 illumination (standard illumination of AM 1.5 G). Best device performances were found as 10.33% for P1, 6.43% for P2 and, 1.63% for P5. The optimization process is still in progress for P3, P4, and P6.


Investigation the effect of π bridge and side chain on photovoltaic properties of benzodithiophene and quinoxaline based conjugated polymers
Taşkaya Aslan, Sultan; Alemdar, Eda; Hacıefendioğlu, Tuğba; UDUM, YASEMİN; Toppare, Levent Kamil; Yıldırım, Erol; Çırpan, Ali (2022-04-15)
© 2022 Elsevier LtdA series of donor–acceptor type alternative polymers containing 2D-BDT and 1D-BDT as the donors and quinoxaline as the acceptor were successfully obtained by Stille coupling reactions. Synthesized polymers containing selenophene and thiophene as π-bridges in their backbones and 2-ethylhexylselenophene and 2-ethylhexylalkoxy side groups on the BDT structure were named as P1, P2, P3 and P4, respectively. Eonsetox and Eonsetred were investigated for P1, P2, P3, and P4, respectively. Onset ox...
Synthesis of selenophene substituted benzodithiophene and fluorinated benzothiadiazole based conjugated polymers for organic solar cell applications
Cevher, Duygu; Taşkaya Aslan, Sultan; Bolayır, Eda; Hizalan Ozsoy, Gonul; UDUM, YASEMİN; Yıldırım, Erol; Toppare, Levent Kamil; Çırpan, Ali (2021-12-01)
A series of alternating conjugated copolymers which contain selenophene modified benzodithiophene and fluorine bearing benzothiadiazole have been synthesized via Stille polycondensation reaction to investigate the effect of the number of fluorine atoms substituted to the benzothiadiazole. Three different polymers, PBDTSe-BT, PBDTSe-FBT and PBDTSe-FFBT, were reported and their electrochemical, spectroelectrochemical, and photovoltaic behaviors were examined. Density functional theory calculations were perfor...
Synthesis of bistriphenylamine- and benzodithiophene-based random conjugated polymers for organic photovoltaic applications
CETIN, Asli; ISTANBULLUOGLU, Cagla; HACIOGLU, Serife Ozdemir; CEVHER, ŞEVKİ CAN; Toppare, Levent Kamil; Çırpan, Ali (2017-11-15)
In this study, donor-acceptor random polymers containing benzotriazole acceptor and bistriphenylamine and benzodithiophene donors, P1 and P2, were successfully synthesized by Stille coupling polymerization. The effect of bistriphenylamine moiety and thiophene -conjugated linker on electrochemical, spectroelectrochemical, and optical behaviors of the polymers were investigated. Optoelectronic properties and photovoltaic performance of the polymers were examined under the illumination of AM 1.5G, 100 mWcm(-2)...
Syntheses of conjugated polymers and investigation the effect of gold nanoparticle - thiol interaction for organic solar cell application
Gülmez, Selin; Çırpan, Ali; Department of Chemistry (2022-8-31)
In this thesis, five benzo[c][1,2,5] thiadiazole-based conjugated polymers were synthesized. Four of them were synthesized via Stille and Suzuki coupling reactions and the remaining one was synthesized by post-polymerization. The effect of functional groups of the tip of the alkyl chain was analyzed. Moreover, thiol group and gold nanoparticle interaction on the organic solar cell efficiency for P1-SH were investigated. Electronic and optical band gaps of polymers were found as 1.85/1.81, 1.95/1.85, 1.83/1....
Synthesis, characterization and electrochromic properties of a near infrared active conducting polymer of 1,4-di(selenophen-2-yl)-benzene
Aydemir, Kadir; Tarkuc, Simge; Durmus, Asuman; Günbaş, Emrullah Görkem; Toppare, Levent Kamil (Elsevier BV, 2008-04-15)
A novel selenophene-based monomer, 1,4-di(selenophen-2-yl)-benzene (DSB), was synthesized via Stille coupling reaction of 1,4-dibromobenzene and tributyl(2-selenophenyl)stannane. Conducting polymer (PDSB) was prepared electrochemically in the presence of tetrabutylammonium hexafluorophosphate (TBAPF(6)) as the supporting electrolyte in dichloromethane (DCM). The resulting conducting polymer was characterized by Cyclic Voltammetry, Fourier Transform Infrared and Ultraviolet-visible spectroscopy. Spectroelect...
Citation Formats
O. Karakurt, “Synthesis, characterization and photovoltaic properties of benzo[c][1,2,5]oxadiazole based conjugated polymers for organic solar cells,” M.S. - Master of Science, Middle East Technical University, 2021.