초록문의 abstract@kcsnet.or.kr

결제문의 member@kcsnet.or.kr

현재 가능한 작업은 아래와 같습니다.
  • 09월 04일 17시 이후 : 초록수정 불가능, 일정확인 및 검색만 가능

제114회 대한화학회 학술발표회, 총회 및 기기전시회 안내 First-principles calculation of charge transfer rate of push-pull copolymer

2014년 9월 1일 16시 06분 04초
PHYS.P-476 이곳을 클릭하시면 발표코드에 대한 설명을 보실 수 있습니다.
10월 15일 (수요일) 16:00~19:00
저자 및
정은환, 류설1, Yves Lansac2, 장윤희3,*
광주과학기술원(GIST) 신소재공학과, Korea
1조선대학교 화학과, Korea
2Université François Rabelais, 37200 Tours, France
3광주과학기술원(GIST) 신소재공학, Korea
※ 국외소속으로 등록된 저자의 승인여부는 최소 3일이내 발표자 email로 알려드립니다.
승인 1건
Low-band-gap copolymers having both electron-rich and electron-deficient units, so-called push-pull-type copolymers, are promising donor materials for bulk heterojunction organic photovoltaic cells. Two push-pull copolymers 1-2, in which a common pushing group, cyclopentadithiophene (CPDT), is connected to a different pulling group, either benzothiadiazole (BT) or thienopyrroledione (TPD), are compared. Their structure, electronic structure and optical properties are calculated with density functional theory (DFT) and time-dependent DFT (TDDFT) methods. Both 1 (CPDTBT) and 2 (CPDTTPD) show a highly planar backbone structure. The absorption spectra predicted from the calculated HOMO and LUMO energy levels match very well the experimental UV/visible spectra of both polymers. From those HOMO and LUMO energy levels, almost the same power conversion efficiencies (PCE) are predicted for both polymers, but in fact a higher PCE has been observed for 2 than for 1 especially after a morphology control. It appears that a better-controlled morphology of 2, which is not considered in electronic structure calculations, improves the charge transfer and in turn the PCE. Therefore, in this work, we compare the charge transfer properties of the copolymers 1-2 by (1) building a set of π-π stacked pairs of their monomer and dimer units, (2) performing DFT calculations on those pairs to obtain their intermolecular interactions, reorganization energies and the transfer integrals, and finally (3) estimating their charge transfer rates and mobilities. Indeed, the copolymer 2 exhibit a higher hole mobility than the copolymer 1.