title: New Terthiophene-Conjugated Porphyrin Donors for Highly Efficient Organic Solar Cells.
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 π-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-C71-butyric acid methyl ester (PC71BM) characteristics of bicontinuous, interpenetrating networks required for efficient charge separation and transportation.
authors.affiliation: Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , 381 Wushan Road, Guangzhou 510640, China.
authors.forename: Liangang
authors.initials: L
authors.lastname: Xiao
authors.affiliation: Institute of Molecular Functional Materials, Research Centre of Excellence for Organic Electronics, Department of Chemistry and Institute of Advanced Materials, Hong Kong Baptist University , Waterloo Road, Kowloon Tong, Hong Kong China.
authors.forename: Song
authors.initials: S
authors.lastname: Chen
authors.affiliation: Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , 381 Wushan Road, Guangzhou 510640, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Gao
authors.affiliation: Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , 381 Wushan Road, Guangzhou 510640, China.
authors.forename: Xiaobin
authors.initials: X
authors.lastname: Peng
authors.affiliation: Materials Sciences Division, Lawrence Berkeley National Lab , Berkeley, California 94720, United States.
authors.forename: Feng
authors.initials: F
authors.lastname: Liu
authors.affiliation: Institute of Polymer Optoelectronic Materials and Devices, State Key Laboratory of Luminescent Materials and Devices, South China University of Technology , 381 Wushan Road, Guangzhou 510640, China.
authors.forename: Yong
authors.initials: Y
authors.lastname: Cao
authors.affiliation: Department of Applied Biology and Chemical Technology, The Hong Kong Polytechnic University , Hung Hom, Hong Kong China.
authors.forename: Wai-Yeung
authors.initials: WY
authors.lastname: Wong
authors.affiliation: Institute of Molecular Functional Materials, Research Centre of Excellence for Organic Electronics, Department of Chemistry and Institute of Advanced Materials, Hong Kong Baptist University , Waterloo Road, Kowloon Tong, Hong Kong China.
authors.forename: Wai-Kwok
authors.initials: WK
authors.lastname: Wong
authors.affiliation: Institute of Molecular Functional Materials, Research Centre of Excellence for Organic Electronics, Department of Chemistry and Institute of Advanced Materials, Hong Kong Baptist University , Waterloo Road, Kowloon Tong, Hong Kong China.
authors.forename: Xunjin
authors.initials: X
authors.lastname: Zhu
keywords: molecular packing; organic solar cells; peripheral substitutions; porphyrin; terthiophene