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In recent years, studies on conjugated polymers have strengthened the researchers' thought that such polymers can play an essential role in developing new generation energy storage devices. Hence conjugated polymer supercapacitor studies have accelerated. In the present work, selenophene-containing conjugated polymers previously synthesized via palladium-catalyzed Suzuki polymerization reaction were used in the preparation of conjugated polymer-based supercapacitor electrodes. The structure and surface morphology of conjugated polymers were determined using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The selenophene-containing two conjugated polymer electrodes (ITO/Polymer) were fabricated. The electrochemical behavior of the conjugated polymer electrodes was evaluated through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). The specific capacity of ITO/CP1 electrode at 5 mV/s are 161.2 and 47 (Fg(-1)) for 0.1 mg and 1.2 mg, respectively. The specific capacity of ITO/CP2 at 5 mV/s electrode are 511 and 108.85 (Fg(-1)) for 0.08 mg and 0.70 mg, respectively. The time constants were determined as 10 and 625 ms for ITO/CP1 and CP2/ITO electrodes, respectively.

The current–voltage (I−V) and capacitance–voltage (C−V) characteristics of the organic heterojunction diode were investigated in a wide temperature range from 80 to 320 K and frequency range from 10 kHz to 1 MHz, respectively. Alternative to the copolymer partner poly(3-hexylthiophene) (P3HT) to [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), poly((9,9-dioctylfluorene)-2,7-diyl-(4,7-bis(thien-2-yl)2-dodecyl-benzo[1,2,3]triazole)) (named as copolymer in this work) was adapted to the bulk-heterojunction layer in the organic diode. Together with the use of Lif/Al bilayer electrode, the diode was fabricated as in the form of Al/LiF/copolymer:PCBM/PEDOT:PSS/ITO/glass. Under the applied bias voltage, this organic-based diode shows two-orders of magnitude rectifying behavior. According to thermionic emission (TE) model, the diode parameters such as saturation current, barrier height and ideality factor were determined and parasitic resistances were also extracted from the conventional ohmic relation. As to the temperature dependency of the diode parameters and their response to the temperature variation, barrier inhomogeneity, surface state and series resistance effects were found in dominant behavior on the current flow. The conduction mechanism was modeled by assuming low-barrier patches around the main barrier that supports TE at low temperatures and their distribution was expressed by a Gaussian function. In addition, series resistance values were detailed depending on temperature using Cheung’s model. C−V analysis was performed to evaluate the distribution of surface states at the interface as a function of frequency. Based on the C−V plots, the effects of charges at these traps were observed especially at low frequencies. Additionally, from these results, Fermi level, surface potential and donor concentration values were evaluated in a wide frequency range.

Color-changing energy storage devices that can easily communicate with the user carry the potential to be integrated into smart electronics. In this work, nanocomposite electrochromic supercapacitor electrodes were fabricated with silver nanowire (Ag NW) network electrodes and a green to transmissive electrochromic polymer, PDOPEQ. High transparency and conductivity of Ag NW network current collectors allowed the fabrication of electrochromic supercapacitors and investigation of the spectroelectrochemical and electrochemical properties of the PDOPEQ. Previously reported electrochromic properties such as long term electrochromic switching stability and vibrant color change for PDOPEQ were well transferred into electrochromic capacitors. Investigated electrochromic supercapacitors changed their color from vibrant green to transparent with superior characteristics. Specific capacitance of the fabricated nanocomposite electrodes was calculated as 61.5 F g(-1) at a current density of 0.1 A g(-1) and to the best of our knowledge, one of the highest capacity retention value was obtained upon 20000 galvanostatic charge-discharge cycles. With these color options and electrochemical performance, investigated conducting polymer (CP) holds strong promise to be used in electrochromic supercapacitors. (C) 2017 The Electrochemical Society. All rights reserved.

Polypyrrole and its copolymers with terepthalic acid bis-(2-thiophen-3-yl-ethyl)ester, (P(TATE-co-Py) were characterized by direct pyrolysis mass spectrometry to investigate the effects of dopant on thermal stability and conductivity. Conductivities of the films were measured with four-probe technique, and the results were compared with the pyrolysis data. In general, an increase in conductivity was detected as the stability of dopant increased. The extent of doping and the strength of interaction between the dopant and the polymer were decreased upon copolymerization with terepthalic acid bis-(2-thiophen-3-yl-ethyl)ester.

In the context of low cost flexible display device technology, requirements can be fulfilled with accessible multi-colored electrochromic polymers. Here, we report the synthesis and electrochromic properties of two spray processable, ambipolar, fluorescent and multi-color to transmissive electrochromic polymers. Polymers, PTBTPh and PTBTTh, have multi-colored oxidation states and easily accessible n-doped states, which allowed us to achieve transmissive films in a low working potential. Electrochemical and spectral results showed that both polymers are potential materials for electrochromic display devices.

D-A-D-type polymers are of high interest in the field of photovoltaics and electrochromism. In this study we report the synthesis and electrochemical properties of PPyBT along with its photophysical properties and photovoltaic performance. PPyBT is soluble in common organic solvents and both n- and p-type dopable, which is a desired property for conjugated polymers. During electrochemistry studies, the onset potentials of the polymer were determined as +0.2V for oxidation and -1.4V for reduction. Using these values, HOMO and LUMO energy levels were calculated. The photovoltaic properties of PPyBT were also studied. PL studies showed that there is a charge transfer between PPyBT (donor) and PCBM (acceptor).

A recently synthesized conducting polymer [poly(2-dodecyl-4,7-di(thiophen-2-yl)-2H-benzo[d][1,2,3] triazole (PTBT)] was tested as a platform for biomolecule immobilization. After electrochemical polymerization of the monomer (TBT) on graphite electrodes, immobilization of glucose oxidase (GOx, beta-D-glucose: oxygen-1-oxidoreductase, EC 1.1.3.4) was carried out. To improve the interactions between the enzyme and hydrophobic alkyl chain on the polymeric structure, GOx and isoleucine (Ile) amino acid were mixed in sodium phosphate buffer (pH 7.0) with a high ionic strength (250 x 10(-3) M). The solution is then casted on the polymer film, and the amino groups in the protein structure were crosslinked using glutaraldehyde (GA) as the bifunctional agent. Finally, the surface was covered with a perm-selective membrane. Consequently, cross-linked enzyme crystal (CLEC) like assembles with regular shapes were observed after immobilization. Microscopic techniques such as scanning electron microscopy (SEM) and fluorescence microscopy were used to monitor the surface morphologies of both the polymer and the bioactive layer. Electrochemical responses of the enzyme electrodes were measured by monitoring O-2 consumption in the presence of glucose at -0.7 V. The optimized biosensor showed a very good linearity between 0.05 and 2.5 x 10(-3) M with a 52 s response time and a detection limit (LOD) of 0.029 x 10(-3) M to glucose. Also, kinetic parameters, operational and storage stabilities were determined. K-m and I-max values were found as 4.6 x 10(-3) M and 2.49 mu A, respectively. It was also shown that no activity was lost during operational and storage conditions. Finally, proposed system was applied for glucose biomonitoring during fermentation in yeast culture where HPLC was used as the reference method to verify the data obtained by the proposed biosensor.

Electrochemical copolymerization of 1-(phenyl)-2,5-di(2-thienyl)-1H-pyrrole (PTP) with 3,4-ethylenedioxy thiophene (EDOT) was carried out in acetonitrile (AN)/NaClO4/LiClO4 (0-1 M) solvent-electrolyte couple via potentiodynamic electrolysis. Characterizations of the resulting copolymer were performed via cyclic voltammetry (CV), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and spectroelectrochemical analysis. Spectroelectrochemical analyses show that the copolymer of PTP with EDOT has an electronic band gap (due to pi to pi* transition) of 1.9 eV at 480 nm, with a claret red in the fully reduced form and a blue color in the fully oxidized form. Via kinetic studies, the optical contrast (Delta T %) was found to be 8% for P(PTP-co-EDOT). Results showed that the time required to reach 95% of the ultimate transmittance was 1.7 s for the copolymer.

Immobilization of whole viable Pseudomonas fluorescens cells was achieved on a graphite electrode modified with a thiophene-based conducting polymer. Microbial electrodes were constructed by the entrapment of bacterial cells on conducting copolymer matrix using a dialysis membrane. The biosensor was characterized using glucose as the substrate. As well as analytical characterization, effects of electropolymerization time, pH and temperature on the sensor response were examined. Finally, operational stability was also tested.

An amperometric biosensor for the detection of phenolic compounds was developed based on the immobilization of tyrosinase within an Os-complex functionalized electrodeposition polymer. Integration of tyrosinase within the redox polymer assures efficient catechol recycling between the enzyme and the polymer bound redox sites. The non-manual immobilization procedure improves the reproducibility of fabrication process, greatly reduces the desorption of the enzyme from the immobilization layer, and, most importantly prevents fast inactivation of the enzyme by its substrate due to fast redox cycling.

This report highlights the synthesis of only the second green polymer in the literature, which possesses superior properties over the first: a highly transmissive light blue color in the oxidized state with high optical contrast and excellent switching properties.

A dipyrrolyl monomer was synthesized via the reaction between 4-pyrrol-1-yl phenol and decanedioyl dichloride. The electrochemical behavior of this monomer was studied. Polymerization of decanedioic acid bis-(4-pyrrol-1-yi-phenyl) ester (DAPE) was achieved by chemical and constant current electrolyses methods. Copolymerization of DAPE with thiophene was performed by constant potential electrolysis in acetonitrile-tetrabutylammonium tetrafluoroborate (TBAFB), dichloromethane-TBAFB, solvent-electrolyte couples. The chemical structures and properties were investigated by Fourier transform infrared spectroscopy, nuclear magnetic resonance spectroscopy, differential scanning calorimetry and thermal gravimetry analysis. The conductivities of the samples were measured by a four-probe technique.

Polysiloxane-polypyrrole graft copolymers have been synthesized by a series of chemical reactions and subsequent electropolymerization. First, the hydrosilation of 4-vinyl aniline by dimethyl-methylhydrosiloxane copolymer gave the corresponding aminophenyl functional polydimethylsiloxane (PDMS-NH2). The side chain pyrrole functionalized. polysiloxanes were then prepared by the reaction of PDMS-NH2 with glycidylpyrrole. Finally, the synthesis of graft copolymers of polysiloxane and pyrrole has been achieved electrochemically by using two different electrolytes, p-toluene sulfonic acid (PTSA) and tetrabutylammonium tetrafluoroborate (TBAFB). Characterization of these graft copolymers were performed by a combination of techniques consisting of scanning electron microscopy (SEM), thermal gravimetry (TGA), differential scanning calorimetry (DSC) analyses and FT-IR studies. The conductivities were measured by four-probe technique.

Mixed matrix composite membranes of a conducting polymer, polypyrrole (PPy), and an insulating polymer, polybisphenol-A-carbonate (PC) were prepared by a combined in-situ polymerization and solvent evaporation. Mixed matrix composite membranes were synthesized to combine the good gas transport properties of conductive polymer, PPy, with good mechanical properties of PC.

The gas sensing ability of electrochemically prepared pure polyaniline and polyaniline-poly(bisphenol-A carbonate) films is investigated. The responses of the composite films to several vapours are more well defined and reproducible compared to the pure conducting polymer. The changes in resistance as determined via the two-probe technique are well defined down to a level of 0.025% vol./vol. ammonia. The possible reason for such a difference is discussed. The structure of the composite is examined through pyrolysis FT-IR studies.

Electroinitiated copolymerization of indene with β-methoxystyrene was carried out at 0°C and five different potentials. Monomer consumption was studied by cyclic voltammetry. It is known that, when the difference between oxidation potentials of two monomers is large, polymerization potential affects copolymer composition. In the present study indene and β-methoxystyrene were selected because their oxidation potentials are almost equal, ca. + 1.40 V. The effect of polymerization potential on copolymer composition was studied. The copolymer composition did not change with polymerization potential, a novel result, for these monomers with almost equal oxidation peak potentials. The total reacted monomer concentration did not change with polymerization potential either. The amount of precipitated polymer, however, increased with polymerization potential.

[1,2,5]Kalkojenazolo[3,4-f]benzo[1,2,3]triazol üniteleri yapılarının iki tarafındaki elektron eksikliği sayesinde bulundukları konjuge polimerlerin bant aralıklarını daraltan güçlü elektron akseptör parçalardır. Bu çalışmada, bahsedilen parçaların donör-akseptör tipi konjuge polimerlere dahil edilmesiyle akseptör gücünün optoelektronik özellikler üzerindeki etkileri amaçlanmış ve araştırılmıştır. Kalkojenazol yapılarının merkezindeki kalkojen atomunun polimerlerin optoelektronik özellikleri üzerindeki etkileri karşılaştırılması için sülfür ve selenyum olarak farklılaştırılmıştır. Bu nedenle, yakın kızılötesi (NIR) bölgesinde soğuran özgün konjuge donör-akseptör tipi iki kopolimer, akseptör olarak [1,2,5]kalkojenazolo[3,4-f]-benzo[1,2,3]triazol türevlerini ve donör olarak benzoditiyofen içeren ve tiyofen π-köprüsü ile ayrılmış yapısı ile dizayn edilmiş ve Stille polikondenzasyon reksiyonu ile sentezlenmiştir. Dallanmış alkil grubu (genişletilmiş 2-oktil-1-dodesil alkil grubu; -C8C12) 5H- [1,2,3]triazolo[4',5':4,5]benzo[1,2-c][1,2,5]tiyadiazol ve 5H-[1,2,3]triazolo[4',5':4,5]benzo[1,2-c][1,2,5]selenadiazol yapılarına polimerlerin çözünürlüğünün geliştirilmesi ve işlenebilirliğinin kolaylaştırılması için takılmıştır ve bu sayede cihaz yapılarının iyileştirilmesi amaçlanmıştır. Güçlü elektron-çeken üniteler absorpsiyon özelliklerinde azımsanmayacak değişikliklere, NIR bölgesine kadar uzanan geniş absorpsiyon aralığında π–π* geçişi yanı sıra molekül içi yük transferi (ICT) bantını teşvik ederek sebep olmuştur. Elde edilen çözünür polimerler HOMO ve LUMO enerji seviyelerini belirlemek amacıyla dönüşümlü voltometri ile karakterize edilmiştir ve sırası ile PSBT için -5.00 eV ve -3.92 eV olarak ve PSeBT için -4.86 eV and -4.04 eV olarak bulunmuştur. Kopolimerlerin elektronik bant aralıkları sırası ile PSBT için 1.08 eV ve PseBT için 0.82 eV olarak hesaplanmıştır. Son olarak, kükürt türevinden daha düşük bant aralığı ve tüm RGB arasında daha iyi renk geçişi yapabilme özelliklerinden dolayı SeBT polimeri kullanılarak bir elektrokromik cihaz kurulmuştur ve karakterizasyonları yapılmıştır. [1,2,5]Chalcogenazolo[3,4-f]benzo[1,2,3]triazole units are strong electron-acceptor moieties that narrow the band gap of resulting conjugated polymers due to the electron deficiency on both sides of their structure. In this study, the effect of acceptor strength on optoelectronic properties were aimed and investigated by incorporating these moieties into donor-acceptor type conjugated polymers. Central chalcogen atom of the chalcogenazole linkage differentiated as sulfur and selenium to compare their effects on the optoelectronic properties of the polymers. Therefore, two novel conjugated near-IR (NIR) absorbing donor–acceptor type copolymers comprising [1,2,5]chalcogenazolo[3,4-f]-benzo[1,2,3]triazole derivatives as the acceptors and benzodithiophene as the donor, spaced with thiophene as the π-bridge, were designed and synthesized via Stille polycondensation reaction. Branched alkyl chains (the extended 2-octyl-1-dodecyl alkyl chain; -C8C12) were substituted to 5H-[1,2,3]triazolo[4',5':4,5]benzo[1,2-c][1,2,5]thiadiazole and 5H-[1,2,3]triazolo[4',5':4,5]benzo[1,2-c][1,2,5]selenadiazole for enhanced solubility of polymers which ease the processability hence device constructions. The strong electron-withdrawing units lead to a substantial change on the absorption properties via promoting the intramolecular charge transfer (ICT) band alongside the π–π* transition with a wide range of absorption extended to the NIR region. The resultant soluble polymers were characterized via cyclic voltammetry to determine HOMO and LUMO energy levels as -5.00 eV and -3.92 for PSBT and -4.86 eV and -4.04 eV for PSeBT, respectively. Electronic band gaps of the copolymers were calculated as 1.08 eV for PSBT and 0.82 eV for PSeBT, respectively. Finally, an electrochromic device (ECD) was constructed and characterized using the polymer PSeBT, due to its lower band gap and better switching colors displayed in all RGB than its sulfur analogue. 120

Sensör, batarya, fotovoltaik cihazlar ve OLED'ler gibi birçok elektronik cihazda iletken gümüş mürekep kullanma ihtiyacı günden güne artmaktadır. Bunun yanısıra, giyilebilir teknolojilerde de esnekliği göz önünde bulundurulduğunda iletken gümüş mürekkep kullanımının önemli bir yeri vardır. Bu tür cihazlar düşük sıcaklıkta kürlenebilen gümüş pastalara ihtiyaç duymaktadır. Bazı gümüş mürekkepler kürlenmek için 900 ˚C'ye ihtiyaç duymaktadır, fakat bu sıcaklık PET ve kumaşlar için uygun değildir. PET ve kumaş gibi materyaller için düşük sıcaklıkta kürlenebilen bir mürekkebe ihtiyaç duyulmaktadır. Bu mürekkeplerin yapımında gümüş nanoparçacık kullanımı sinterleme ve alt tabakaya mürekkebin yapışmasında zorluk çıkartmaktadır. Bu sorunlarla başa çıkmak için gümüş nanoparçacıklar yerine gümüş nanoteller kullanılmıştır. Gümüş nanoteller; optik geçirgenlik, yapışma gücü, uyumluluk ve iletkenlik açısından gümüş nanoparçacığa kıyasla daha elverişlidir.Gümüş nanotellerin ağ yapısı halindeykenki optic geçirgenliği ve iletkenliği daha fazladır; ayrıca gümüş nanoteller gümüş nanoparçacıklara kıyasla daha geniş bir yüzeye sahip olduğu için yüzeye tutunması daha güçlüdür. Bu tezin amacı; gümüş nanotelleri kullanarak düşük sıcaklıkta kürlenebilen gümüş mürekkep sentezlemektir. Conductive inks are used extensively in electronic devices like sensors, batteries, photovoltaic devices, antenna and organic light emitting diodes. These inks typically made from silver. Wearable technology is another industry which requires inks to be flexible. These devices need low temperature cured silver pastes. Low temperature pastes typically make use of silver nanoparticles. These pastes have some problems with sintering and substrate adhesion. In this thesis, to overcome these problems, silver nanowires are used to formulate pastes. Conductivity, bonding strength, flexibility, transparency and compliance of the silver nanowire pastes were determined. Promising performance of was obtained from silver nanowire pastes due to the one dimensional nature of the nanowires in terms of adhesion to fabric surface. Silver nanowires have a big area to adhere, network form of them is more conductive and transparent than network form of silver nanoparticles. The aim of this study is fabrication of low temperature silver paste by synthesis long silver nanowires. 79

Donor–akseptör (D–A) tipi konjüge polimerler organik ışık yayan diyotlar, güneş pilleri, elektrokromik cihazlar ve organik transistörler gibi çeşitli uygulamalarda kullanılmaktadır. Benzazole içeren iletken polimerler kuvvetli intramoleküler yük transfer özelliği ve yüksek fotovoltaik performasından dolayı düşük bant aralıklı donör malzemeler olarak kullanabildiği için son yıllarda popüler olmuşlardır. Kuvvetli elektron alıcı ve verici özelliğe sahip üniteler, D-A tipi polimerlerin bant aralığı ve HOMO enerji seviyesini düşürmek için gereklidirler. Akseptör ünitelerine alkoksi grupların ikame edilmesi polimelerin daha iyi çözünürlüğe ve daha yüksek moleküler ağırlığa sahip olmalarını sağlarken flor atomunun ikame edilmesi elektron yoğunluğunu azaltarak akseptör ünitelerinin daha kuvvetli hale gelmesini sağlar. Bu tezde, 2,1,3-benzazol ünitelerine hem flor hem de alkoksi grupları ikame edilmiştir. Benzazole ve izoindigo yapı-özellik ilişkisini incelemek amacıyla Stille ve Suzuki kenetlenme reaksiyonları kullanılarak donör üniteleri ile eşleştirilmiştir. Diğer yandan, çevre dostu bir metot olan Doğrudan Heteroarilasyon Polimerleştirme (DHAP) yöntemi ile yeni polimerler elde edilmiştir. Değişik donör ve akseptör üniteleri eşleştirilerek polimerlerin yapı-özellik ilişkileri incelenecek ve polimerler optoelektronik uygulamalarda kullanılacaktır. Polimerlerin molekül ağırlığı GPC analizi ile incelenmiştir. İndirgenme ve yükseltgenme davranışları dönüşümlü voltametri ile çalışılmıştır. Polimerler optoelektronik uygulamalarda aktif tabaka olarak kullanılmıştır. Termal ve çözelti tavlama yöntemlerinin morfolojiye etkisine bakılmıştır. Kalınlık ve morfoloji optimizasyonundan sonra, pilin üretimi ve akım/gerilim özelikleri azot dolu eldivenli kabin sisteminde gerçekleştirilmiştir. Güneş pillerinin (ITO/PEDOT: PSS/polimer:PCBM/ metal) analizleri güç çevirim verimi AM 1,5G aydınlatma ile hesaplanmıştır 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 necessary to lower the band gaps and HOMO energy levels of D–A polymers. Alkoxy substitution to the acceptor groups provides polymers better solubility and higher molecular weight whereas fluorine substitution increases the strength of the acceptors via lowering electron density. In this thesis, 2,1,3-benzazole moieties were substituted with alkoxy and fluorine groups. Benzazole and isoindigo were coupled with several donor groups via both Stille and Suzuki polycondensation reactions to investigate structure-property relationships. On the other hand, Direct Heteroarylation Polymerization (DHAP) was also performed to obtain new polymers via an eco-friendly method. Molecular weights of polymers were investigated with GPC analysis. Oxidation and reduction behavior of the polymers were conducted using cyclic voltammetry. Polymers were used as active layers in optoelectronic applications. The effect of thermal and solvent annealing on morphology were determined. After optimizing thickness and morphologies of polymer:PCBM, device production and current/voltage property measurements were performed in a nitrogen-filled glove box system. The analysis of the photovoltaic devices ITO/ PEDOT:PSS/ Polymer: PCBM/ Metal) were achieved by means of the energy conversion efficiency measured under standard AM 1.5G illumination. 262

İlk uygulamada, organik ışık saçan diyotlarda kullanılmak üzere fenanthroimidazol ile birleştirilmiş benzotriazol tabanlı polimerik zincire sahip üç farklı polimer sentezlenmiştir. P1 ile üretilmiş elektroluminans cihazı üstün özellikler göstermiştir. 3,02 eV ile en yüksek bant aralığına sahip P1 tabanlı cihaz en yüksek 3,01 cd/A luminans verimi ile 140.180 cd/m2 luminans değerine sahip olmuştur. İkinci kısımda, lakkas tabanlı katekol biyosensörü için monomer M1 sentezlemiş olup ketondan (M1) oksime (M2) ve enamine (M3) fonksiyonellendirilmiştir. Enzim immobilizasyonu gluteraldehit ile üzeri çıplak elektrokimyasal polimer kaplı camsı karbon elektrota çapraz bağlanmıştır. M1 tabanlı polimer herhangi bir yardımcı maddeye ihtiyaç duymadan 0.005-0.175 mM doğrusal aralığı ve 9.86 μM saptama sınırı gibi üstün özelliklere sahip olmuştur. Son bölümde, kalkojenlerin ve ayrıca electron itici/çekici grupların etkilerini incelemek amacıyla güneş pillerinde kullanılacak dört farklı polimer sentezlenmiştir. PO diğerlerine kıyasla en yüksek güç çevirim verimi % 4.72'ye ulaşmıştır. Polimerlerin ön araştırma sonuçları güneş hücreleri için gelecek vaad eden sonuçlar göstermiştir. Bunlardan ayrı iki farklı konjüge polimerler daha absorpsiyon aralıklarını kızıl ötesi bölgeye genişletmek amacıyla sentezlenmiştir. Optik bant aralıkları konjüge polimerlerin sırasıyla PIQBDT ve PIQCAR'ın absopsiyon eğrilerindeki başlangıç (onset) değerleri olan 870 ve 760 nm kullanılarak 1,42 ve 1,63 eV olarak hespalanmıştır. Son çalışma ise plasmonik nanoparçacıklara kovalent olarak bağlanabilecek polimerlerin sentezini kapsamaktadır. Bu sayede plasmonik nanoparçacıkların güneş hücreleri içindeki morfolojik dağılımını polimerin yakın çevresinde bulunmasını sağlayacaktır. In the first application, to investigate the organic light emitting diode device performances three different polymers were synthesized in which fused phenantroimidazole ring was combined with benzotirazole based polymeric backbone. P1 incorporated electroluminescent device exhibited superior performance. The highest luminance efficiency for P1 based device was 3.01 cd/A with a luminance value of 140,180 cd/m2. In the second part, monomer M1 was synthesized and functionalized from ketone (M1) to oxime (M2) and enamine (M3) for laccase based catechol biosensors. Laccase immobilized by crosslinking with glutaraldehyde on bare polymer coated galssy carbon electrode. M1 based electrode exhibited superior performance linear range between 0.005-0.175 mM with detection limit of 9.86 μM without need of any additional support material. In the final part, four similar polymers were synthesized where the effect of chalcogens or effect of electron donating/withdrawing ability of substituents were investigated separately. PO gave the highest power conversion efficiency among others with a value of 4.72 %. Hence preliminary studies of polymers exhibited promising properties for efficient solar cells. Two more polymers were synthesized to enlarge the absorption of conjugated polymers to infrared region. Optical band gaps of polymers were calculated from absorption on set values of 870 and 760 nm as 1.42 and 1.63 eV respectively for PIQBDT and PIQCAR. The last study covered the synthesis of polymeric material, which can covalently bond to plasmonic nanoparticles. In this way morphological distribution of plasmonic nanoparticles could be in close proximity to polymer in solar cells. 231

Bu tezde glikoz tespiti için bir konjuge polimer, kitosan ve çok duvarlı karbon nanotüplerden oluşan bir amperometrik biyosensör imal edilmiştir. Konjuge polimerler benzersiz elektronik özellikleri, yüksek stabiliteleri ve işlenebilirlikleri ile biyoalgılama platformları geliştirme alanında yeni bir çağ açtılar. Konjuge polimerler hem biyoalgılama elemanları için immobilizasyon matrisi olarak ve hem de biyoalgılama cihazlarında transdüser olarak görev yaparlar. Ek bir modifikasyon materyali olarak kitosan, mükemmel film biçimlendirilebilirliği, biyouyumluluk, biyobozunurluk ve toksik olmayanlık gibi gelecek vaadeden özellikleri nedeniyle, önerilen biyosensörün yapısına katıldı. Kitosan, konjuge polimer ile birlikte mükemmel bir immobilizasyon matrisi olarak görev yaptı ve biyosensörün stabilitesini ve duyarlılığını arttırdı. Çok duvarlı karbon nanotüpler, elektrokimyasal algılama cihazlarında da yaygın olarak kullanılmaktadırlar. Sebebi üstün elektrokimyasal özellikleri sayesinde biyosensörlerin tepki performanslarını arttırmalarıdır. Ayrıca, enzimlerin katalitik aktiviteleri ve stabilitelerini koruyarak destekleyici matris malzemeleri olarak da gelecek vaat etmektedirler. Bu açıdan, elektropolimerizasyon yoluyla fonksiyonel bir monomer ile bir grafit elektrotun modifiye edilmesi ve ardından kitosan/çok duvarlı karbon nanotüp çözeltisi ile döküm yapılmasıyla; 0.032 mM algılama sınırına, 63.76 uAmM-1cm-2 duyarlılık değerine ve 0.01-0.75 mM glikoz için iyi bir lineer tepki aralığına sahip bir biyosensör imal edilmiştir. Ayrıca biyosensör 0.05 mM gibi bir KMapp değeri ile umut vadeden kinetik parametreler ortaya koymaktadır. Yüzey değişikliklerinin araştırılması için, dönüşümlü voltametri ve SEM teknikleri kullanılmıştır. Ayrıca, önerilen biyosensörün uygulanabilirliğini kanıtlamak için sistem ticari bir içecek numunesi ile test edilmiştir. In this thesis an amperometric biosensor consisting of a conjugated polymer, chitosan and multi-walled carbon nanotubes constructed for the detection of glucose. Conjugated polymers have opened a new era for the development of biosensing platforms with their unique electronic properties, high stabilities and processabilities. They serve both as immobilization matrices for biorecognition elements and as transducers in biosensing devices. As an additional modification material, chitosan was participated in the construction of the proposed biosensor due to its promising properties such as excellent film formability, biocompatibility, biodegradability, and nontoxicity. Chitosan served as a great immobilization matrix together with the conjugated polymer and improved the stability and sensitivity of the biosensor. Multi-walled carbon nanotubes have also extensively used in electrochemical sensing devices since they improve the response performances of biosensors due to their superior electrochemical properties. Furthermore, they are also promising as supporting matrix materials while preserving the catalytic activity and stability of enzymes. From this point of view, by modifying a graphite electrode with a monomer via electropolymerization followed by casting with CHIT/MWCNTs solution, the proposed biosensor was fabricated having a good linear response for glucose between 0.01-0.75 mM with a detection limit of 0.032 mM and the sensitivity value of 63.76 μAmM-1cm-2. Moreover, the biosensor presented promising kinetic parameters with the KMapp value of 0.05 mM. For investigating the surface modifications, cyclic voltammetry and SEM techniques were utilized. Besides, in order to prove the applicability of the proposed biosensor, the system was tested with a commercial beverage sample. 68

Bu çalışmada, akseptör grup olarak benzotiyadiazol ve benzotriazol, donör grup olarak ise benzoditiyofen içeren iki özgün polimerin fotovoltaik performansları incelenmiştir. Buna ek olarak, tiyofen ve selenofen π köprülerinin, polimerlerin optik, elektrokimyasal ve optoelektronik özelliklerine etkileri çalışılmıştır. Selenofen içeren P1 ve tiyofen içeren P2 için optik bant aralığı değerleri sırasıyla 1.63 eV ve 1.73 eV olarak bulunmuştur. Polimerler, UV-VIS-NIR spektroskopisi, dönüşümlü voltammetri (CV), jel geçirgenlik kromatografisi (GPC) ve termal analiz gibi yöntemlerle karakterize edilmiştir. Organik güneş gözeleri, N2 ile doldurulmuş eldivenli kabin sisteminde oluşturulmuş ve karakterize edilmiştir. Göze yapımında ITO/PEDOT:PSS/Polimer:PC71BM/LiF/Al şeklinde düz cihaz mimarisi kullanılmış olup, polimerler elektron donörü, PC71BM ise elektron akseptörü olarak kullanılmıştır. Standard AM 1.5 G ışıması (100 mW/cm2) ölçümler sonucunda, P1 ve P2 bazlı organik güneş gözeleri için maksimum güç dönüşüm verimi değerleri sırasıyla %1.60 ve %3.83 olarak kayıtlara geçmiştir. In this study two novel random polymers, comprising benzothiadiazole and benzotriazole as the accepting units and benzodithiophene as the donor unit, were examined in terms of their photovoltaic performance. Moreover, effects thiophene and selenophene π bridges on optical, electrochemical and optoelectronic properties of the polymers were investigated. Optical band gap values of selenophene bearing P1 and thiophene P2 were found as 1.63 eV and 1.73 eV, respectively. Characterization of polymers via UV-Vis-NIR spectroscopy, cyclic voltammetry (CV), gel permeation chromatography (GPC) and thermal analysis were carried out. Organic solar cells (OSCs) were constructed and characterized in N2 filled glove box. While the polymers act as electron donors, PC71BM was the electron acceptor in OSCs with the device structure of ITO/PEDOT:PSS/Polymer:PC71BM/LiF/Al. As a consequence of measurements under standard AM 1.5 G illumination (100 mW/cm2), the highest power conversion efficiency values were recorded as 1.60% and 3.83 % for P1 and P2 based OSCs, respectively. 88

Gerçekleştirilen bu tezde, iki yeni benzoditiyofen ve benzotriazol içeren sıralı kopolimerlerin elektrokimyasal, optiksel ve fotovoltaik çalışmaları araştırılmıştır. Güçlü elektron verme özelliği ve yüzelsel yapısı ile benzoditiyofen donör olarak kullanılmıştır. Benzotriazol ise elektronca eksik yapısı ile akseptör olarak kullanılmıştır. Buna ek olarak, л köprüsünün etkisini görmek için tiyofen (P1) ve selenofen (P2) üniteleri donör ve akseptör ünitelerinin arasına yerleştirilmiştir. Elektrokimyasal çalışmalar iki polimerin de pozitif ve negatif doplanabildiklerini göstermiştir. Ayrıca, polimerlerin enerji seviyelerini hesaplamak için dönüşümlü voltametri kullanılmıştır. Ters organik güneş gözesi için ITO / ZnO / POLİMER:PC71BM / MoO3 / Ag dizilimi kullanılmıştır. Akım Yoğunluğu-Voltaj ölçümleri standart AM 1.5G aydınlatma ile yapılmıştır. Kalınlık ve morfoloji incelemeleri AFM ve TEM ile belirlenmiştir. Yapılan birçok optimizasyon sonucunda, P1 ve P2 polimerlerinin güç dönüşüm verimlilikleri sırasıyla %1.30 ve %1.02 olarak hesaplanmıştır. 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 and acceptor units. Electrochemical studies revealed that both polymers have ambipolar character. Cyclic voltammetry analysis were carried out to calculate HOMO and LUMO energy levels of polymer P1 and P2. Inverted organic photovoltaic applications of polymers were constructed as following ITO / ZnO / POLYMER:PC71BM / MoO3 / Ag. The J-V measurements of the photovoltaic devices were performed under the standard AM 1.5G illumination. AFM and TEM techniques were used in order to examine thickness and morphology of the polymer films. As a result of several optimization studies, power conversion efficiencies were achieved as 1.30% for P1 and 1.02% for P2, respectively. 74

Biyosensörlerin yüzey özellikleri performansları üzerinde çok önemli bir rol oynar. Bu nedenle, bu tezde, konjuge polimer esaslı amperometrik biyosensörlerin yüzey tasarımında farklı makroyapıların kullanımı araştırılmıştır. İletken polimerler (CPs) iletkenlik, yüksek mekanik dayanıklılık ve işlenilebilirlik özelliklerinden dolayı biyosensörlere üstün nitelikler sağlarlar. Ayrıca, ftalosiyaninler (Pcs) de zengin redoks kimyası ve elekrokimyasal kararlılık gibi elektronik özelliklerinden dolayı biyosensör uygulamaları için uygun moleküllerdir. Ek olarak, dendrimerler üç boyutlu yapılarındaki dahili boşluk oranından dolayı konuk moleküllerin yerleşmesi için uygun konak moleküllerdir. Özellikle, poli(amidoamin) (PAMAM) yapısı biyomoleküllerin bağlanmasını güçlendiren terminal amino grupları içermesi sebebiyle biyosensör uygulamalarında etkili bir malzemedir. Ayrıca, çok duvarlı karbon nanotüpler (MWCNTs) mekanik mukavemet, stabilite ve yüksek iletkenlik özelliklerine ek olarak biyouyumluluk gösterdikleri için biyosensör uygulamalarında yaygın olarak kullanılmaktadır. Bütün bu yapıların avantajlarından yararlanarak, CPs/MWCNTs/ZnPc ve CPs/MWCNTs/PAMAM kombinasyonlarında iki yeni glikoz biyosensörü oluşturulmuş, operasyonel ve kinetik parametreleri ile yüzey özellikleri karakterize edilmiş ve biyosensörler gerçek zamanlı analizler için başarılı bir şekilde test edilmiştir. In this thesis, the use of different macrostructures in the surface design of conjugated polymer based amperometric biosensors was investigated since surface properties play a crucial role in the performance of biosensors. Conjugated polymers (CPs) provide biosensors superior features since they exhibit conductivity, high mechanical strength and processability. Moreover, phthalocyanines (Pcs) are promising molecules for biosensor applications due to their electronic properties, rich redox chemistry and high electrochemical stability. In addition to phthalocyanines, dendrimers are suitable host molecules for accommodation of guest molecules due to their three-dimensional structure having an internal void space. Especially, poly(amidoamine) (PAMAM), can be used in biosensor applications since it contains a number of terminal amino groups which enhances the attachment of biomolecules. Multi-walled carbon nanotubes (MWCNTs) have also extensively used in biosensor applications since they are compatible with biomolecules in addition to their mechanical strength, stability and conductivity properties. By taking the advantages of these materials, two novel glucose biosensors; CPs/MWCNTs/ZnPc and CPs/MWCNTs/PAMAM were fabricated. Their operational and kinetic parameters and surface features were characterized and the biosensors were successfully tested for real time analyses. 94