Synthesis of new conjugated donor-acceptor type polymers for photovoltaic device applications

Akpınar, Hava Zekiye
Electrochromism and photoelectric effect are the mostly investigated areas of conducting polymers. In electrochromism, electrochemical parameters of the polymers are firstly examined. Spectroelectrochemical studies are performed with specified wavelengths. Parameters, such as optical contrast and switching times of the polymer films are explored. In bulk heterojunction polymer solar cells, semiconducting polymer materials in combination with fullerene are used as the active layer. Photons are absorbed by conjugated polymer and strongly bounded excitons are formed. In order to efficiently separate the bounded electron hole pairs, HOMO and LUMO levels of the polymer and fullerene should be compatible with each other. The performance of the devices is also highly dependent on the molecular structure of the polymer side chains. In this thesis study, five novel conjugated polymers containing donor-acceptor units such as thiazolothiazole, thiophene, furan, benzotriazole and fluorene were synthesized via Suzuki and Stille coupling polymerizations. Electrochemical and optical properties of the polymers were examined and bulk heterojunction organic photovoltaic devices were fabricated using (C 61) fullerene. Solar cell parameters such as open circuit voltage, short circuit current density, fill factor and power conversion efficiency were measured.


Inverted organic solar cell applications of benzodithiophene and benzotriazole bearing alternating copolymers
Bolayır, Eda; Toppare, Levent Kamil; Department of Chemistry (2018)
In this thesis, electrochemical, optical and photovoltaic studies of two novel benzodithiophene and 1,2,3-benzotriazole bearing alternating copolymers were investigated. Benzodithiophene which has a strong electron donating ability and planar structure was used as the donor moiety. On the other hand, benzotriazole was used as an acceptor moiety due to its electron deficient nature. In order to determine the effect of л-bridges, thiophene (P1) and selenophene (P2) moieties were incorporated between the donor...
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Yaşa, Mustafa; Toppare, Levent Kamil; Department of Polymer Science and Technology (2017)
Donor-Acceptor (D-A) type conjugated polymers are very popular for potential applications such as organic light emitting diodes, solar cells, electrochromic devices and organic field effect transistors. In literature, cyclopentadithiophene and its derivatives are commonly used electron donor units for organic solar cells. The incorporation of selenium atom into polymer backbone results in low band gap polymers as compared to sulfur and oxygen counterparts. In this study, selenophene containing conjugated po...
Synthesis, characterizations and photovoltaic applications of dithienothiophene and benzotriazole containing conjugated polymers
Cevher, Şevki Can; Çırpan, Ali; Toppare, Levent Kamil; Department of Chemistry (2013)
Fused bithiophene containing conjugated polymers are recently used in different applications; for example organic light emitting diodes, solar cells, electrochromic devices and organic field effect transistors. Fused bithiophene derivatives increase the planarity, charge mobility and decrease band gap when incorporated into the polymer backbone. Connecting atom between the bithiopheneunit can be phosphorous, silicon, nitrogen and sulphur. In this thesis, dihienothiophene was coupled with benzotriazole via S...
Thermal degradation of polythiophene-natural rubber and polythiophene-synthetic rubber conducting polymer composites
Hacaloğlu, Jale; Akbulut, Ural; Toppare, Levent Kamil (1997-01-01)
Thermal degradation of conducting polymer composites of polythiophene and rubbers was studied by direct and indirect pyrolysis mass spectrometry techniques. The samples were prepared by electrooxidation of polythiophene using natural rubber or synthetic rubber as the insulating matrix. Presence of decomposition products which were not observed during pyrolysis of pure polythiophene and rubbers, and disappearance of rubber-based pyrolysis mass peaks, together with changes in thermal stability and behaviour, ...
Radiation of dipoles in multilayered cylinder with ferrite layer
Aydin, O; Hizal, A (1996-07-26)
Radiation characteristics of infinitesimal dipole in multilayered circular cylindrical structure including gyromagnetic media are investigated. Transversal field equations in spectral domain are obtained for gyromagnetic medium in cylindrical coordinates. These expressions are formed into a set of linear differential equations. The solution at each layer is expressed in terms of state transition matrices. Fields are matched at the interfaces. Far fields are evaluated asymptotically. The effects of changing ...
Citation Formats
H. Z. Akpınar, “Synthesis of new conjugated donor-acceptor type polymers for photovoltaic device applications,” Ph.D. - Doctoral Program, Middle East Technical University, 2015.