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Morphological studies of small-molecule solar cells: nanostructural engineering via solvent vapor annealing treatments

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Abstract

Fine-tuning nano/micro-structural morphologies and their depth studies in small-molecule solar cells are key parameters in elevating device performances. In the current work, we focused on controlling the morphology of a small-molecule organic photovoltaic by treating its active layer film with solvent vapor annealing (SVA). For this project, the devices were made of all-small-molecule p-DTS(FBTTh2)2:PC71BM heterojunction films processed using different solvents for the vapor annealing. The different solvents resulted in different nano-domain packing structures and segregated phase separation as evidenced by detailed two-dimensional grazing-incidence wide-angle X-ray scattering (2D-GIWAXS) and atomic force microscopy (AFM) analyses. From the data, we demonstrated a correlation between the nanostructural morphology of the active layer film and the performance of the device and found an SVA condition that produced a p-DTS(FBTTh2)2:PC71BM blend system yielding an improved device performance.

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Acknowledgements

This work was supported by a Grant from the Center for Advanced Soft Electronics (2011-0031639) under the Global Frontier Research Program of the Ministry of Education, Science, and Technology, Korea and a National Research Foundation of Korea (NRF) Grant funded by the Korea government (MSIP) (2017R1C1B2002888).

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Author notes

  1. Yu Jin Kim

    Present address: Argonne National Laboratory, Center for Nanoscale Materials, 9700 S. Cass Ave., Lemont, IL, 60439, USA

Authors and Affiliations

  1. POSTECH Organic Electronics Laboratory, Department of Chemical Engineering, Pohang University of Science and Technology, Pohang, 790-784, Republic of Korea

    Yu Jin Kim & Chan Eon Park

  2. Department of Polymer Science and Engineering, Korea National University of Transportation, 50 Daehak-ro, Chungju, Republic of Korea

    Tae Kyu An

  3. Department of IT Convergence, Korea National University of Transportation, 50 Daehak-ro, Chungju, Republic of Korea

    Tae Kyu An

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  1. Yu Jin Kim
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Correspondence to Tae Kyu An or Chan Eon Park.

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Kim, Y.J., An, T.K. & Park, C.E. Morphological studies of small-molecule solar cells: nanostructural engineering via solvent vapor annealing treatments. J Mater Sci 52, 13173–13182 (2017). https://doi.org/10.1007/s10853-017-1407-9

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