Design, synthesis and characterization of 2,1,3-benzothiadiazole comprising polymers: the effect of bridging units on the optoelectronic properties and opv device construction

Download

12626072.pdf

Date

2021-2-10

Author

Zeytun Karaman, Cansu

Metadata

Show full item record

This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.

Item Usage Stats

580
views

342
downloads

Recently, conjugated polymers have obtained increasing popularity in a wide range of application areas such as electrochromic (EC) devices, biosensors, organic solar cells (OPVs) and organic light-emitting diodes (OLEDs). This popularity results from ease of processability, a good charge transporting capability, and broad optical absorption ability of the conjugated polymers. 2,1,3 benzothiadiazole has been commonly used in D-A type conjugated polymers since it is one of the strongest acceptor groups resulting in low band gap polymers. Fluorination of polymer backbone has appeared to be a promising approach for the development of semiconducting polymers for photovoltaic devices. Altering frontier molecular orbitals via fluorination could lead to better device performance. Alkoxy substitution is also performed to provide better solubility and high molecular weight for polymers. Besides, fluorene is used as a donor due to its high electron density and larger absorption wavelength. Lately, bridging groups are introduced into the polymer backbone to obtain higher intermolecular charge transport, higher absorption in the spectrum, and lower band gap. In this thesis, 2,1,3-benzothiadiazole coupled with bridging groups: furan, thiophene, 3-hexylthiophene, selenophene, and thienothiophene via Stille reaction. These groups are used to investigate the changes in electronic, optic, intermolecular charge transport, and photovoltaic properties of the polymers. GPC analyses are done to determine molecular weights of polymers. Redox behaviors of the polymers are studied using cyclic voltammetry. After optimizing thickness and morphologies of polymer: PCBM, device construction, and current-voltage property measurements are conducted in a nitrogen-filled glovebox system. The analysis of the photovoltaic devices (ITO/PEDOT:PSS/Polymer:PC70BM/Metal) is performed by means of the energy conversion efficiency measured under standard AM 1.5G illumination.

Subject Keywords

2,1,3-Benzotiadiazol, Donor-Acceptor Approach, Conjugated Conducting Polymers, Organic Solar Cell

URI

https://hdl.handle.net/11511/89570

Collections

Graduate School of Natural and Applied Sciences, Thesis

Suggestions

OpenMETU
Core

Synthesis and optoelectronic applications of benzotriazole and dibenzosilole based alternating copolymers Erlik, Ozan; Çırpan, Ali; Department of Chemistry (2014) Dibenzosilole synonym of silafluorene based polymers have been extensively used as the donor moiety in D-A approach for several years for optoelectronic applications like electrochromic (EC) devices, organic light emitting diodes (OLEDs), organic field effect transistors (OFETs) and most widely organic photovoltaics (OPVs). Moreover, chalcogenophenes such as thiophene and selenophene are used as an energy bridge between the donor and acceptor units to adjust the electronic and optical properties of the conj...
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...
Design, syntheses and structure-property relationships of benzazole and isoindigo comprising conducting polymers/ Göker, Seza; Toppare, Levent Kamil; Department of Chemistry (2019) Donor–acceptor (D–A) conjugated polymers have been widely used for potential applications such as organic light emitting diodes, solar cells, electrochromic devices and organic field effect transistors. Benzazole comprising conducting polymers are popular for the last few decades since they can be used as low-band-gap donor materials because of their strong intramolecular charge transfer characteristics and excellent photovoltaic performances. Strong electron-donating and withdrawing building blocks are nec...
Synthesis of novel diketopyrrole and selenophene containing nir absorbing polymers and their application in bulk-heterojunction solar cells Öklem, Gülce; Günbaş, Emrullah Görkem; Department of Polymer Science and Technology (2017) DPP-based conjugated polymers are recently used in organic light emitting diodes, electrochromic devices, organic field effect transistor and organic solar cell applications. Their advantageous properties, such as broad optical absorption in Near Infra Red (NIR) region, high charge carrier mobility and good film forming ability make them an excellent choice for generation of highly efficient solar cells. In this thesis, using donor-acceptor approach (D-A) we aimed to synthesize novel polymers with furan bas...
A triazoloquinoxaline and benzodithiophene bearing low band gap copolymer for electrochromic and organic photovoltaic applications HACIOGLU, Serife O.; UNLU, Naime A.; AKTAS, Ece; HIZALAN, Gonul; Yildiz, Esra D.; Çırpan, Ali; Toppare, Levent Kamil (2017-06-01) A new triazoloquinoxaline and benzodithiophene based copolymer was synthesized to investigate its electro-chemical, optical and photovoltaic behaviors. According to the polymer design, combination of two acceptor units (benzotriazole and quinoxaline) which contribute imine bonds to the structure and a triazoloquinoxaline unit for enhancing electron accepting ability was pursued. As a result of electrochemical studies, the copolymer PTQBDT has a low lying HOMO energy level as - 5.23 eV which increases the ch...

Citation Formats

C. Zeytun Karaman, “Design, synthesis and characterization of 2,1,3-benzothiadiazole comprising polymers: the effect of bridging units on the optoelectronic properties and opv device construction,” M.S. - Master of Science, Middle East Technical University, 2021.