Efficient and stable organic solar cells via full coating are highly desirable. Poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) is a classic conducting polymer complex and widely used for hole collection in fully printable devices. However, PEDOT:PSS is typically dispersed in water and exhibits strong acidity that deteriorates device efficiency and stability. Here we report an alcohol-dispersed formulation (denoted as PEDOT:F) by adopting perfluorinated sulfonic acid ionomers as counterions. The ionomers have a special advantage of having two solubility parameters and can be dispersed in water or alcohols, which enables us to prepare PEDOT:F formulations dispersed in alcohols. The alcohol-dispersed formulation has good wetting properties and low acidity, which avoids the drawbacks of aqueous PEDOT:PSS. Fully printable organic photovoltaics (from bottom electrode to top electrode) based on PEDOT:F were obtained with a power conversion efficiency of 15% and could retain 83% of the initial efficiency under continuous illumination at maximum power point tracking for 1,330 h.
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The datasets analysed and generated during the current study are included in the paper and its Supplementary Information. Source data are provided with this paper.
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The work was supported by the National Natural Science Foundation of China (grant numbers 51973074, 51773072 and 61804060) and the special innovation funds of Wuhan National Laboratory for Optoelectronics. The authors would also like to thank the Analytical and Testing Center of Huazhong University of Science and Technology for providing the facilities to conduct characterizations.
The authors declare no competing interests.
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(Fig. 2c) Source data of absorbance spectra of ZnO films with and without PEDOT:F or PEDOT:PSS coating. d, Statistical source data of work function of PEDOT:F films.
(Fig. 3b) Statistical source data of PCE of cells with different active layers. c–e, Source data of J–V characteristics of cells with PEDOT:F processed from different conditions and statistical source data of PCE of cells with PEDOT:F processed from different conditions.
(Fig. 4b) Source data of J–V characteristics of fully coated solar cells and statistical source data of PCE of fully coated solar cells. c, Source data of PCE evolution as a function of time under illumination of fully coated solar cells. e, Source data of J–V characteristics of fully coated solar modules.
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Jiang, Y., Dong, X., Sun, L. et al. An alcohol-dispersed conducting polymer complex for fully printable organic solar cells with improved stability. Nat Energy 7, 352–359 (2022). https://doi.org/10.1038/s41560-022-00997-9