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Pairing of near-ultraviolet solar cells with electrochromic windows for smart management of the solar spectrum

An Author Correction to this article was published on 18 September 2017

This article has been updated


Current smart window technologies offer dynamic control of the optical transmission of the visible and near-infrared portions of the solar spectrum to reduce lighting, heating and cooling needs in buildings and to improve occupant comfort. Solar cells harvesting near-ultraviolet photons could satisfy the unmet need of powering such smart windows over the same spatial footprint without competing for visible or infrared photons, and without the same aesthetic and design constraints. Here, we report organic single-junction solar cells that selectively harvest near-ultraviolet photons, produce open-circuit voltages eclipsing 1.6 V and exhibit scalability in power generation, with active layers (10 cm2) substantially larger than those typical of demonstration organic solar cells (0.04–0.2 cm2). Integration of these solar cells with a low-cost, polymer-based electrochromic window enables intelligent management of the solar spectrum, with near-ultraviolet photons powering the regulation of visible and near-infrared photons for natural lighting and heating purposes.

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Figure 1: Proposed management of the solar spectrum.
Figure 2: Chemical structures and thin-film optoelectronic properties.
Figure 3: Active-layer characterization.
Figure 4: Solar cell characterization.
Figure 5: Area scaling of solar cells.
Figure 6: Large-area solar cell with an alternative electrode.
Figure 7: Electrochromic window (ECW) characterization.
Figure 8: Combined ECW and PV stack optical transmittance.

Change history

  • 18 September 2017

    In the version of this Article originally published, Fig. 4f was incorrect. This error has now been corrected.


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N.C.D. acknowledges financial support from the National Science Foundation Graduate Research Fellowship Program under Grant No. DGE 1148900. We (N.C.D., M.S.-E. and Y.-L.L.) acknowledge support from NSF MRSEC funding through Princeton Center for Complex Materials (DMR-1420541) and the Wilke Family Fund administered by the School of Engineering and Applied Science at Princeton University. A.K. acknowledges support from the National Science Foundation under Grant No. DMR-1506097. We thank M. Panzer and H. Qin of Tufts University for valuable discussions regarding ionogels, and G. Man of Princeton University for assistance with UPS/IPES analysis.

Author information




N.C.D., M.S.-E. and Y.-L.L. wrote the manuscript; N.C.D. synthesized molecular semiconductors; X.L. and A.K. provided UPS/IPES measurements and analysis; N.C.D. and J.G. fabricated and characterized PV cells; M.S.-E. synthesized PANI-PAAMPSA; M.S.-E. and A.L. fabricated and characterized ECWs; M.S.-E. and N.D. integrated ECW and PV components for solar-powered ECW demonstration. N.Y. conducted TEM sample preparation and imaging. All authors discussed the results and reviewed the manuscript.

Corresponding author

Correspondence to Yueh-Lin Loo.

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The authors declare no competing financial interests.

Supplementary information

Supplementary Information

Supplementary Figures 1–10 and Supplementary Tables 1 and 2. (PDF 985 kb)

Supplementary Video 1

Demonstration of a 2.25 cm2 solar-powered electrochromic window comprising stacked films of PANI-PAAPMSA and PEDOT:PSS separated by a gel electrolyte. The switching of this window between its coloured and bleached states is driven by a 1.38 cm2 D/A1 cell under 1 sun AM1.5G illumination. (MP4 19631 kb)

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Davy, N., Sezen-Edmonds, M., Gao, J. et al. Pairing of near-ultraviolet solar cells with electrochromic windows for smart management of the solar spectrum. Nat Energy 2, 17104 (2017).

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