• Bulletin of the Korean Chemical Society
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• 제33권3호
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• pp.1029-1036
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• 2012

Push-pull-type copolymers - low-band-gap copolymers of electron-rich fused-ring units (such as cyclopentadithiophene; CPDT) and electron-deficient units (such as benzothiadiazole; BT) - are promising donor materials for organic solar cells. Following a design principles proposed in our previous study, we investigate the electronic structure of a series of new CPDTBT derivatives with various electron-withdrawing groups using the time-dependent density functional theory and predict their power conversion efficiency from a newlydeveloped protocol using the Scharber diagram. Significantly improved efficiencies are expected for derivatives with carbonyl [C=O], carbonothioyl [C=S], dicyano [$C(CN)_2$] and dicyanomethylene [C=$C(CN)_2$] groups, but these polymers with no long alkyl side chain attached to them are likely to be insoluble in most organic solvents and inapplicable to low-cost solution processes. We thus devise several approaches to attach alkyl side chains to these polymers while keeping their high efficiencies.

• 공업화학
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• 제27권5호
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• pp.467-471
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• 2016

새로운 전자 받개인 6,7-difluoro-2,3-dihexylquinoxaline을 이용하여 유기 태양 전지형 고분자를 개발하였다. Fluorene과 6,7-difluoro-2,3-dihexylquinoxaline으로 Suzuki polymerization방법을 이용하여 낮은 HOMO 에너지를 가지는 PFDTQxF 고분자를 합성하였다. 필름상태의 PFDTQxF은 368과 493 nm에서 두 개의 흡광도를 보였다. PFDTQxF의 HOMO와 LUMO 에너지는 각각 -5.55와 -3.91 eV을 나타내었다. PFDTQxF의 태양전지 소자는 0.47 V의 $V_{OC}$와 $4.48mA/cm^2$의 $J_{SC}$와 0.32의 FF를 가지고 있어 0.78%의 에너지 효율을 나타내었다.