Journal: ACS applied materials & interfaces
Article Title: New Terthiophene-Conjugated Porphyrin Donors for Highly Efficient Organic Solar Cells.
PMID/MRN: 27731985
Publication Date: 2016-Nov-09
Abstract:
To mimic the natural photosynthetic systems utilizing chlorophylls to absorb light and store light energy, two new porphyrin-based small molecules of PTTR and PTTCNR have been developed for photovoltaic applications. The highest power conversion efficiency of 8.21% is achieved, corresponding to a short-circuit current of 14.30 mA cm -2 , open-circuit voltage of 0.82 V, and fill factor of 70.01%. The excellent device performances can be ascribed to the engineering of molecule structure and film morphology. The horizontal conjugation of 3,3?-dihexyl-terthiophene to porphyrin-core with the vertical aliphatic 2-octylundecyl peripheral substitutions, can not only effectively increase the solar flux coverage between the conventional Soret and Q bands of porphyrin unit, but also optimize molecular packing through polymorphism associated with side-chains and the linear ¹-conjugated backbones. And the additive of 1,8-diiodooctane and subsequent chloroform solvent vapor annealing facilitate the formation of the blend films with [6,6]-phenyl-C 71 -butyric acid methyl ester (PC 71 BM) characteristics of bicontinuous, interpenetrating networks required for efficient charge separation and transportation.