Flexible organic photovoltaics based on water-processed silver nanowire electrodes

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Abstract

A key feature of organic electronic devices is their mechanical flexibility. However, the performance of flexible organic optoelectronic devices still lags behind the performance of devices on rigid substrates. This is due, in particular, to the lack of flexible transparent electrodes that simultaneously offer low resistance, high transparency and a smooth surface. Here, we report flexible transparent electrodes created using water-processed silver nanowires and a polyelectrolyte. Due to ionic electrostatic charge repulsion, the nanowires form grid-like structures in a single step, leading to smooth, flexible electrodes that have a sheet resistance of around 10 Ω □−1 and a transmittance of around 92% (excluding the substrate). To illustrate the potential of the approach in organic electronics, we use the flexible electrodes to create organic photovoltaic devices. The devices are tested with different types of donors and acceptors, and exhibit performance comparable to devices based on commercial rigid electrodes. Furthermore, flexible single-junction and tandem devices achieve power conversion efficiencies of 13.1% and 16.5%, respectively.

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Fig. 1: Three typical patterns and their percolation.
Fig. 2: SEM images of FlexAgNEs.
Fig. 3: Optoelectric and mechanical performance of FlexAgNEs.
Fig. 4: OPV applications using FlexAgNEs.
Fig. 5: Performance of flexible and rigid OPV devices.

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.

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Acknowledgements

We gratefully acknowledge financial support from MoST (2016YFA0200200), NSFC (91633301, 21421001, 51873089, 51773095) of China, Tianjin city (17JCJQJC44500, 17JCZDJC31100) and 111 Project (B12015).

Author information

Y.C. conceived and designed the research. Y.S. fabricated the FlexAgNEs and flexible OPV devices and carried out all of the performance studies. L.M. and Y.Z. fabricated and characterized the OPV devices based on rigid ITO electrodes. M.C. and H.G. synthesized 3TT-FIC and O6T-4F. K.Z. and Y.S. built the theoretical physical model. Z.S., S.L., H.W. and J.L. conducted partial characterization of the FlexAgNEs. The manuscript was mainly prepared by Y.C., Y.S., C.L. and X.W., and all authors participated in the manuscript preparation and commented on the manuscript.

Correspondence to Yongsheng Chen.

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Competing interests

A patent (application no. 201910514527.9) has been filed for the flexible electrodes and devices.

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Supplementary Information

Supplementary Tables 1–12 and Figs. 1–22.

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Sun, Y., Chang, M., Meng, L. et al. Flexible organic photovoltaics based on water-processed silver nanowire electrodes. Nat Electron 2, 513–520 (2019) doi:10.1038/s41928-019-0315-1

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