Published date: Oct 14 2018

Journal Title: KnE Materials Science

Issue title: Sino-Russian ASRTU Conference Alternative Energy: Materials, Technologies, and Devices

Pages: 56-65

DOI: 10.18502/kms.v4i2.3038

W J Wangweijia.wang@nwpu.edu.cn

L Song

X H Ren

H Q Fan

J F Moulin

P Müller-Buschbaum

A facile and efficient route is developed to improve the power conversion efficiency of poly(3-hexylthiophene-2,5-diyl):[6, 6]-phenyl-C61 butyric acid methyl ester (P3HT:PCBM) solar cells by processing solvent additive 1,8-octanedithiol (ODT) in the bulk heterojunction systems. The influence of ODT on polymer surface and inner
morphology, crystallinity, and quantitative molecular miscibility of P3HT and PCBM is studied. The results show that ODT enhances the phase separation of P3HT and PCBM and the P3HT crystallinity, increases the solubility of PCBM in P3HT, and reduces the size of amorphous P3HT domains. A high concentration of ODT induces the formation of a PCBM enrichment surface layer, which is beneficial for the device performance.

Keywords: P3HT:PCBM, ODT, TOF-GISANS, morphology, miscibility

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