S-Space College of Engineering/Engineering Practice School (공과대학/대학원) Dept. of Material Science and Engineering (재료공학부) Theses (Master's Degree_재료공학부)
Effects of Different Chalcogen Atom Substitution in Electron Rich Unit of Isoindigo-based Conjugated Copolymer on Photovoltaic Properties
- 공과대학 재료공학부
- Issue Date
- 서울대학교 대학원
- 학위논문 (석사)-- 서울대학교 대학원 : 재료공학부, 2014. 2. 조원호.
- Recently, chalcogen atom substitution on a conjugated copolymer is investigated to enhance the photovoltaic properties. In this study, new low bandgap conjugated copolymers based on isoindigo and chalcogenophenes (thiophene, selenophene and tellurophene) were synthesized (PIT, PISe and PITe, respectively) to investigate the effects of the chalcogen atom on the photovoltaic properties. The copolymers PISe and PITe show both bathochromic shift and lowering the lowest unoccupied molecular orbital energy level as compared to its thiophene analogue. The solar cell device based on PISe blended with PC61BM exhibits enhanced power conversion efficiency (PCE) of 4.36% with a JSC of 9.38 mA cm2 which is higher than that of PIT. However, PITe shows lower JSC than that of PIT and PISe because of its coarse morphology of the blend.