Manipulation of discrete porphyrin–fullerene nanopillar arrays regulated by the phase separated infiltration of polymer in ternary blended organic thin-films

• Published in: Solar energy materials and solar cells Vol. 140; pp. 428 - 438
• Main Authors: Lee, Jae-hyeong, Jintoku, Hirokuni, Okazaki, Yutaka, Sagawa, Takashi, Takafuji, Makoto, Ihara, Hirotaka
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.09.2015
• Subjects: Arrays; Derivatives; Fullerene; Infiltration; Nanopillar; Nanostructure; Organic solar cell; Phase separation; Photovoltaic cells; Porphyrin; Solar cells; Spin coating; Thin films; Zinc; Fullerene; Nanopillar; Porphyrin; Phase separation; Organic solar cell
• ISSN: 0927-0248; 1879-3398
• DOI: 10.1016/j.solmat.2015.04.043

Fabrication of nanostructure in various typed solar cell is of great importance in terms of the improvement of charge carrier collection and junction area. Here, we report that well-aligned nanopillar arrays are spontaneously developed in the process of the spin coating when a polymer is added to specific porphyrin–fullerene complexes. The nanopillars embedded in the polymers are composed of donor–acceptor assembled systems, based on J-type aggregation of a low-molecular zinc porphyrin derivative and subsequent integration of pyridylated fullerene derivative with coordination and orientation. The diameter and the height of the nanopillars can be controlled by the side chain-length and the concentration of the polymer as well as drying time after the spin coating. Structural, optical, and electrical properties of the nanopillar are also investigated. Finally, improved power conversion efficiency in the porphyrin–fullerene nanopillar is experimentally observed compared to that of the planar thin film prepared under similar conditions. [Display omitted] •Well-defined nanopillars of porphyrin–fullerene are developed by additive polymers.•The discrete nanopillars result from phase-separated infiltration of polymers.•The nanopillars are controlled by side chain-length and concentration of polymers.•Optimized nanopillars lead to a doubling of power conversion efficiencies.