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Monitoring the Effects of Illumination on the Structure of Conjugated Polymer Gels Using Neutron Scattering
Published on: December 21, 2017
Effect of extended π-conjugation structure of donor-acceptor conjugated copolymers on the photoelectronic properties
Meng Wang1, Shaowei Shi, Di Ma
1State Key Laboratory of Organic-Inorganic Composites, Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (P.R. China); Key Laboratory of Carbon Fiber and Functional Polymers, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029 (P.R. China).
Abstract:
New donor-acceptor conjugated copolymers based on alkylthienylbenzodithiophene (BDTT) and alkoxynaphthodithiophene (NDT) have been synthesized and compared with their benzo[1,2-b:4,5-b']dithiophene (BDT)-based analogues to investigate the effect of the extended π conjugation of the polymer main chain on the physicochemical properties of the polymers. A systematic investigation into the optical properties, energy levels, field-effect transistor characteristics, and photovoltaic characteristics of these polymers was conducted. Both polymers demonstrated enhanced photovoltaic performance and increased hole mobility compared with the BDT-based analogue. However, the BDTT-based polymer (with π-conjugation extension perpendicular to main chain) gave the highest power conversion efficiency of 5.07% for the single-junction polymer solar cell, whereas the NDT-based polymer (with π-conjugation extension along the main chain) achieved the highest hole mobility of approximately 0.1 cm(2) V(-1) s(-1) based on the field-effect transistor; this indicated that extending the π conjugation in different orientations would have a significant influence on the properties of the resulting polymers.
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