Polymer light emitting diodes and organic solar cells towards ito free devices and high efficiency devices using electrochemically synthesized polymers /

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2017
Hızalan Özsoy, Gönül
In this study, polymer based solar cells and polymer based light emitting diodes were constructed. In the third and fourth chapters of this study, effect of terminal units and effect of molecular weight on electroluminescence and photovoltaic properties were investigated. Triphenyl end capped polymer P1 based PLED shows luminance value of 10411cd/m2 at 8.5V whereas benzene end capped polymer P2 based PLED has the peak luminance value of 14583cd/m2 at 8V. P2 based photovoltaic devices exhibited superior performance. The best performance device based on P2 achieved a power conversion efficiency (PCE) of 4.11 % with a current density (Jsc) of 6.59 mA/cm2, an open-circuit voltage (Voc) of 0.99 V, and a fill factor (FF) of 0.63. In the fifth chapter, electrochemically synthesized polymers were used in polymer solar cell applications for the first time in literature. P3HT, P3EHT, P3OT, P3DecT and P3DHT were synthesized via electrochemical means. P3EHT based solar cells showed the highest performance. PCE of 2.03% was obtained with a Jsc value of 5.10mA/cm2, Voc value of 0.83V, FF value of 0.48 Ternary solar cells comprising P3EHT, PTB7 and PC71BM was fabricated. PCE value of 6.50 % were achieved with a VOC of 0.72V, JSC of 14.60 mA/cm2 and a FF of 0.62. In the last part of this study, ITO free polymer solar cell and PLED characterizations were carried out. Instead of ITO, Ag nanowires were used as the anode materials in polymer solar cell and polymer light emitting diode applications. 1.13% PCE value was achieved with a VOC of 0.53V, JSC of 4.99mA/cm2 and FF of 0.43 with the device structure of glass/Ag nanowire /P3HT:PC71BM/ LiF /Al. 2625cd/m2 luminance value was obtained with P2 incorporated electroluminescent device with a lower turn on voltage than the one for the ITO based device.

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Citation Formats
G. Hızalan Özsoy, “Polymer light emitting diodes and organic solar cells towards ito free devices and high efficiency devices using electrochemically synthesized polymers /,” Ph.D. - Doctoral Program, Middle East Technical University, 2017.