Synthesis of Benzo[1,2-b:4,5-b']dithiophene-Based Copolymers for Solution Processed Polymer Solar Cells

• Main Authors: Yu-Qi Wu, 吳幼琦
• Other Authors: Chun-Guey Wu
• Format: Others
• Language: zh-TW
• Published: 2015
• Online Access: http://ndltd.ncl.edu.tw/handle/84805805060423635108

碩士 === 國立中央大學 === 化學學系 === 103 === The gradually decrease in the fossil fuel reserves pushes the scientists to search for alternative cost-effective energy resources. Polymer solar cell (PSC) which can be fabricated by spin-coating or roll-to-roll processes is one of the potential further green energy resource due to some advantages such as light-weight, mechanical flexibility, simple processing, low cost, and large-area device can be fabricated by roll-to-roll method. D-A (D: Donor; A: Acceptor) copolymers which generally having high absorption coefficient and adjustable (by donor and acceptor units) optical properties, have been widely used as a P-type semiconductors in the active layer of PSCs. In this thesis we designed and synthesized six new D-A copolymers including PBDTQ、PTBDTQ、PRTBDTQ、PBDTP、PTBDTP and PRTBDTP. These copolymers were synthesized by stille coupling of ((2-ethylhexyl)oxy)benzo[1,2-b:4,5-b']- dithiophene (BDT) donor unit with (4-(hexyloxy)phenyl)quinoxaline (Q) or (4(hexyloxy)phenyl)pyrido[3,4-b]pyrazine (P) acceptor unit. Furthermore, thiophene (T) or 3-hexylthiophene (RT) was also introdued in the main chain to adjust the optical property of the copolymers. The effects of the acceptor unit and side chain modifications on the optoelectronic properties of copolymers were investigated. The bulk heterojunction (BHJ) polymer solar cells based on these copolymers fabricated via solution process were also explored. When PC71BM was used as a N-type material, PTBDTP based inverted BHJ device has the maximum efficiency of 4.40%.