Organic solar cells (OSCs) have been dominated by donor:acceptor blends based on fullerene acceptors for over two decades. This situation has changed recently, with non-fullerene (NF) OSCs developing very quickly. The power conversion efficiencies of NF OSCs have now reached a value of over 13%, which is higher than the best fullerene-based OSCs. NF acceptors show great tunability in absorption spectra and electron energy levels, providing a wide range of new opportunities. The coexistence of low voltage losses and high current generation indicates that new regimes of device physics and photophysics are reached in these systems. This Review highlights these opportunities made possible by NF acceptors, and also discuss the challenges facing the development of NF OSCs for practical applications.
This is a preview of subscription content, access via your institution
Open Access articles citing this article.
Nature Communications Open Access 07 June 2022
Free charge photogeneration in a single component high photovoltaic efficiency organic semiconductor
Nature Communications Open Access 20 May 2022
Nature Communications Open Access 19 May 2022
Subscribe to Nature+
Get immediate online access to Nature and 55 other Nature journal
Subscribe to Journal
Get full journal access for 1 year
only $9.92 per issue
All prices are NET prices.
VAT will be added later in the checkout.
Tax calculation will be finalised during checkout.
Get time limited or full article access on ReadCube.
All prices are NET prices.
Halls, J. J. M. et al. Efficient photodiodes from interpenetrating polymer networks. Nature 376, 498–500 (1995).
Yu, G., Gao, J., Hummelen, J. C., Wudl, F. & Heeger, A. J. Polymer photovoltaic cells: enhanced efficiencies via a network of internal donor-acceptor heterojunctions. Science 270, 1789–1791 (1995).
Gélinas, S. et al. Ultrafast long-range charge separation in organic semiconductor photovoltaic diodes. Science 343, 512–516 (2014).
Schmidt-Mende, L. et al. Self-organized discotic liquid crystals for high-efficiency organic photovoltaics. Science 293, 1119–1122 (2001).
McNeill, C. R. & Greenham, N. C. Conjugated-polymer blends for optoelectronics. Adv. Mater. 21, 3840–3850 (2009).
Zhao, W. et al. Molecular optimization enables over 13% efficiency in organic solar cells. J. Am. Chem. Soc. 139, 7148–7151 (2017).
Zhao, J. et al. Efficient organic solar cells processed from hydrocarbon solvents. Nat. Energy 1, 15027 (2016).
Zhang, S., Ye, L. & Hou, J. Breaking the 10% efficiency barrier in organic photovoltaics: morphology and device optimization of well-known PBDTTT polymers. Adv. Energy Mater. 6, 1502529 (2016).
Liu, J. et al. Fast charge separation in a non-fullerene organic solar cell with a small driving force. Nat. Energy 1, 16089 (2016).
Cheng, P. et al. Realizing small energy loss of 0.55 eV, high open-circuit voltage >1 V and high efficiency >10% in fullerene-free polymer solar cells via energy driver. Adv. Mater. 29, 1605216 (2017).
Chen, S. et al. A wide-bandgap donor polymer for highly efficient non-fullerene organic solar cells with a small voltage loss. J. Am. Chem. Soc. 139, 6298–6301 (2017).
Baran, D. et al. Reduced voltage losses yield 10% efficient fullerene free organic solar cells with >1 V open circuit voltages. Energy Environ. Sci. 9, 3783–3793 (2016).
Bin, H. et al. 11.4% Efficiency non-fullerene polymer solar cells with trialkylsilyl substituted 2D-conjugated polymer as donor. Nat. Commun. 7, 13651 (2016).
Li, Y. et al. Non-fullerene acceptor with low energy loss and high external quantum efficiency: towards high performance polymer solar cells. J. Mater. Chem. A 4, 5890–5897 (2016).
Vandewal, K. et al. Quantification of quantum efficiency and energy losses in low bandgap polymer:fullerene solar cells with high open-circuit voltage. Adv. Funct. Mater. 22, 3480–3490 (2012).
Li, W., Hendriks, K. H., Furlan, A., Wienk, M. M. & Janssen, R. A. J. High quantum efficiencies in polymer solar cells at energy losses below 0.6 eV. J. Am. Chem. Soc. 137, 2231–2234 (2015).
Ran, N. A. et al. Impact of interfacial molecular orientation on radiative recombination and charge generation efficiency. Nat. Commun. 8, 79 (2017).
Ye, L. et al. Manipulating aggregation and molecular orientation in all-polymer photovoltaic cells. Adv. Mater. 27, 6046–6054 (2015).
Jung, J. W. et al. Fluoro-substituted n-type conjugated polymers for additive-free all-polymer bulk heterojunction solar cells with high power conversion efficiency of 6.71%. Adv. Mater. 27, 3310–3317 (2015).
Lee, J. et al. A nonfullerene small molecule acceptor with 3D interlocking geometry enabling efficient organic solar cells. Adv. Mater. 28, 69–76 (2016).
Kang, H. et al. From fullerene–polymer to all-polymer solar cells: the importance of molecular packing, orientation, and morphology control. Acc. Chem. Res. 49, 2424–2434 (2016).
Zhao, W. et al. Fullerene-free polymer solar cells with over 11% efficiency and excellent thermal stability. Adv. Mater. 28, 4734–4739 (2016).
Baran, D. et al. Reducing the efficiency-stability-cost gap of organic photovoltaics with highly efficient and stable small molecule acceptor ternary solar cells. Nat. Mater. 16, 363–369 (2017).
Cnops, K. et al. 8.4% efficient fullerene-free organic solar cells exploiting long-range exciton energy transfer. Nat. Commun. 5, 3406 (2014).
Li, T. et al. Small molecule near-infrared boron dipyrromethene donors for organic tandem solar cells. J. Am. Chem. Soc. 139, 13636–13639 (2017).
Tang, C. W. Two-layer organic photovoltaic cell. Appl. Phys. Lett. 48, 183–185 (1986).
Anthony, J. E., Facchetti, A., Heeney, M., Marder, S. R. & Zhan, X. n-type organic semiconductors in organic electronics. Adv. Mater. 22, 3876–3892 (2010).
Zhang, X. et al. A potential perylene diimide dimer-based acceptor material for highly efficient solution-processed non-fullerene organic solar cells with 4.03% efficiency. Adv. Mater. 25, 5791–5797 (2013).
Lin, Y. et al. A twisted dimeric perylene diimide electron acceptor for efficient organic solar cells. Adv. Energy Mater. 4, 1400420 (2014).
Nielsen, C. B., Holliday, S., Chen, H.-Y., Cryer, S. J. & McCulloch, I. Non-fullerene electron acceptors for use in organic solar cells. Acc. Chem. Res. 48, 2803–2812 (2015).
Guo, Y. et al. Improved performance of all-polymer solar cells enabled by naphthodiperylenetetraimide-based polymer acceptor. Adv. Mater. 29, 1700309 (2017).
Mori, D., Benten, H., Okada, I., Ohkita, H. & Ito, S. Highly efficient charge-carrier generation and collection in polymer/polymer blend solar cells with a power conversion efficiency of 5.7%. Energy Environ. Sci. 7, 2939–2943 (2014).
Li, S. et al. Green-solvent-processed all-polymer solar cells containing a perylene diimide-based acceptor with an efficiency over 6.5%. Adv. Energy Mater. 6, 1501991 (2016).
Gao, L. et al. All-polymer solar cells based on absorption-complementary polymer donor and acceptor with high power conversion efficiency of 8.27%. Adv. Mater. 28, 1884–1890 (2016).
Fan, B. et al. Optimisation of processing solvent and molecular weight for the production of green-solvent-processed all-polymer solar cells with a power conversion efficiency over 9%. Energy Environ. Sci. 10, 1243–1251 (2017).
Granström, M. et al. Laminated fabrication of polymeric photovoltaic diodes. Nature 395, 257–260 (1998).
Lin, Y. et al. An electron acceptor challenging fullerenes for efficient polymer solar cells. Adv. Mater. 27, 1170–1174 (2015).
Li, S. et al. Energy-level modulation of small-molecule electron acceptors to achieve over 12% efficiency in polymer solar cells. Adv. Mater. 28, 9423–9429 (2016).
Yao, H. et al. Achieving highly efficient nonfullerene organic solar cells with improved intermolecular interaction and open-circuit voltage. Adv. Mater. 29, 1700254 (2017).
Cha, H. et al. An efficient, 'burn in' free organic solar cell employing a nonfullerene electron acceptor. Adv. Mater. 29, 1701156 (2017).
Faist, M. A. et al. Competition between the charge transfer state and the singlet states of donor or acceptor limiting the efficiency in polymer:fullerene solar cells. J. Am. Chem. Soc. 134, 685–692 (2012).
Veldman, D., Meskers, S. C. J. & Janssen, R. A. J. The energy of charge-transfer states in electron donor–acceptor blends: insight into the energy losses in organic solar cells. Adv. Funct. Mater. 19, 1939–1948 (2009).
Clarke, T. M. & Durrant, J. R. Charge photogeneration in organic solar cells. Chem. Rev. 110, 6736–6767 (2010).
Kawashima, K., Tamai, Y., Ohkita, H., Osaka, I. & Takimiya, K. High-efficiency polymer solar cells with small photon energy loss. Nat. Commun. 6, 10085 (2015).
Li, S. et al. A spirobifluorene and diketopyrrolopyrrole moieties based non-fullerene acceptor for efficient and thermally stable polymer solar cells with high open-circuit voltage. Energy Environ. Sci. 9, 604–610 (2016).
Nikolis, V. C. et al. Reducing voltage losses in cascade organic solar cells while maintaining high external quantum efficiencies. Adv. Energy Mater. 7, 1700855 (2017).
Rau, U., Blank, B., Müller, T. C. M. & Kirchartz, T. Efficiency potential of photovoltaic materials and devices unveiled by detailed-balance analysis. Phys. Rev. Appl. 7, 044016 (2017).
Goris, L. et al. Absorption phenomena in organic thin films for solar cell applications investigated by photothermal deflection spectroscopy. J. Mater. Sci. 40, 1413–1418 (2005).
Vandewal, K., Tvingstedt, K., Gadisa, A., Inganäs, O. & Manca, J. V. On the origin of the open-circuit voltage of polymer–fullerene solar cells. Nat. Mater. 8, 904–909 (2009).
Tvingstedt, K. et al. Electroluminescence from charge transfer states in polymer solar cells. J. Am. Chem. Soc. 131, 11819–11824 (2009).
Shockley, W. & Queisser, H. J. Detailed balance limit of efficiency of p-n junction solar cells. J. Appl. Phys. 32, 510–519 (1961).
Yao, J. et al. Quantifying losses in open-circuit voltage in solution-processable solar cells. Phys. Rev. Appl. 4, 014020 (2015).
Ross, R. T. Some Thermodynamics of photochemical systems. J. Chem. Phys. 46, 4590–4593 (1967).
Miller, O. D., Yablonovitch, E. & Kurtz, S. R. Strong internal and external luminescence as solar cells approach the Shockley–Queisser limit. IEEE J. Photovolt. 2, 303–311 (2012).
Benduhn, J. et al. Intrinsic non-radiative voltage losses in fullerene-based organic solar cells. Nat. Energy 2, 17053 (2017).
Menke, S. M. et al. Limits for recombination in a low energy loss organic heterojunction. ACS Nano 10, 10736–10744 (2016).
Rao, A. et al. The role of spin in the kinetic control of recombination in organic photovoltaics. Nature 500, 435–439 (2013).
Zheng, Z. et al. Efficient charge transfer and fine-tuned energy level alignment in a thf-processed fullerene-free organic solar cell with 11.3% efficiency. Adv. Mater. 29, 1604241 (2017).
Tamai, Y. et al. Ultrafast long-range charge separation in nonfullerene organic solar cells. ACS Nano https://doi.org/10.1021/acsnano.7b06575 (2017).
Vandewal, K. et al. Efficient charge generation by relaxed charge-transfer states at organic interfaces. Nat. Mater. 13, 63–68 (2014).
Gao, F., Tress, W., Wang, J. & Inganäs, O. Temperature dependence of charge carrier generation in organic photovoltaics. Phys. Rev. Lett. 114, 128701 (2015).
Deibel, C., Strobel, T. & Dyakonov, V. Role of the charge transfer state in organic donor–acceptor solar cells. Adv. Mater. 22, 4097–4111 (2010).
Brédas, J.-L., Norton, J. E., Cornil, J. & Coropceanu, V. Molecular understanding of organic solar cells: the challenges. Acc. Chem. Res. 42, 1691–1699 (2009).
Brédas, J.-L., Sargent, E. H. & Scholes, G. D. Photovoltaic concepts inspired by coherence effects in photosynthetic systems. Nat. Mater. 16, 35–44 (2017).
Falke, S. M. et al. Coherent ultrafast charge transfer in an organic photovoltaic blend. Science 344, 1001–1005 (2014).
Grancini, G. et al. Hot exciton dissociation in polymer solar cells. Nat. Mater. 12, 29–33 (2013).
Jailaubekov, A. E. et al. Hot charge-transfer excitons set the time limit for charge separation at donor/acceptor interfaces in organic photovoltaics. Nat. Mater. 12, 66–73 (2013).
Savoie, B. M. et al. Unequal partnership: asymmetric roles of polymeric donor and fullerene acceptor in generating free charge. J. Am. Chem. Soc. 136, 2876–2884 (2014).
Song, Y., Clafton, S. N., Pensack, R. D., Kee, T. W. & Scholes, G. D. Vibrational coherence probes the mechanism of ultrafast electron transfer in polymer–fullerene blends. Nat. Commun. 5, 4933 (2014).
Bakulin, A. A., Silva, C. & Vella, E. Ultrafast spectroscopy with photocurrent detection: watching excitonic optoelectronic systems at work. J. Phys. Chem. Lett. 7, 250–258 (2016).
Bakulin, A. A. et al. The role of driving energy and delocalized states for charge separation in organic semiconductors. Science 335, 1340–1344 (2012).
Liu, D. et al. Molecular design of a wide-band-gap conjugated polymer for efficient fullerene-free polymer solar cells. Energy Environ. Sci. 10, 546–551 (2017).
Zhang, S. et al. A fluorinated polythiophene derivative with stabilized backbone conformation for highly efficient fullerene and non-fullerene polymer solar cells. Macromolecules 49, 2993–3000 (2016).
Yao, H. et al. A wide bandgap polymer with strong π–π interaction for efficient fullerene-free polymer solar cells. Adv. Energy Mater. 6, 1600742 (2016).
Qian, D. et al. Design, application, and morphology study of a new photovoltaic polymer with strong aggregation in solution state. Macromolecules 45, 9611–9617 (2012).
Salleo, A. Charge transport in polymeric transistors. Mater. Today 10, 38–45 (March, 2007).
Hutchison, G. R., Ratner, M. A. & Marks, T. J. Intermolecular charge transfer between heterocyclic oligomers. effects of heteroatom and molecular packing on hopping transport in organic semiconductors. J. Am. Chem. Soc. 127, 16866–16881 (2005).
Chen, Z. et al. Low band-gap conjugated polymers with strong interchain aggregation and very high hole mobility towards highly efficient thick-film polymer solar cells. Adv. Mater. 26, 2586–2591 (2014).
Zhou, H. et al. Development of fluorinated benzothiadiazole as a structural unit for a polymer solar cell of 7% efficiency. Angew. Chem. Int. Ed. 50, 2995–2998 (2011).
Kim, J. Y. et al. Efficient tandem polymer solar cells fabricated by all-solution processing. Science 317, 222–225 (2007).
You, J. et al. A polymer tandem solar cell with 10.6% power conversion efficiency. Nat. Commun. 4, 1446 (2013).
Gilot, J., Wienk, M. M. & Janssen, R. A. J. Measuring the external quantum efficiency of two-terminal polymer tandem solar cells. Adv. Funct. Mater. 20, 3904–3911 (2010).
Liu, W. et al. Nonfullerene tandem organic solar cells with high open-circuit voltage of 1.97 V. Adv. Mater. 28, 9729–9734 (2016).
Cui, Y. et al. Fine-tuned photoactive and interconnection layers for achieving over 13% efficiency in a fullerene-free tandem organic solar cell. J. Am. Chem. Soc. 139, 7302–7309 (2017).
Cui, Y., Yao, H., Yang, C., Zhang, S. & Hou, J. Organic solar cells with an efficiency approaching 15%. Acta Polym. Sin. https://doi.org/10.11777/j.issn1000-3304.2018.17297 (2017).
Zhang, G. et al. High-performance ternary organic solar cell enabled by a thick active layer containing a liquid crystalline small molecule donor. J. Am. Chem. Soc. 139, 2387–2395 (2017).
Lu, L., Xu, T., Chen, W., Landry, E. S. & Yu, L. Ternary blend polymer solar cells with enhanced power conversion efficiency. Nat. Photon. 8, 716–722 (2014).
Yao, H. et al. Design, synthesis, and photovoltaic characterization of a small molecular acceptor with an ultra-narrow band gap. Angew. Chem. Int. Ed. 56, 3045–3049 (2017).
Lu, H. et al. Ternary-blend polymer solar cells combining fullerene and nonfullerene acceptors to synergistically boost the photovoltaic performance. Adv. Mater. 28, 9559–9566 (2016).
Zhao, W., Li, S., Zhang, S., Liu, X. & Hou, J. Ternary polymer solar cells based on two acceptors and one donor for achieving 12.2% efficiency. Adv. Mater. 29, 1604059 (2017).
Yu, R. et al. Two well-miscible acceptors work as one for efficient fullerene-free organic solar cells. Adv. Mater. 29, 1700437 (2017).
Khlyabich, P. P., Burkhart, B. & Thompson, B. C. Compositional dependence of the open-circuit voltage in ternary blend bulk heterojunction solar cells based on two donor polymers. J. Am. Chem. Soc. 134, 9074–9077 (2012).
Wang, C. et al. Ternary organic solar cells with enhanced open circuit voltage. Nano Energy 37, 24–31 (2017).
Chen, C.-C. et al. High-performance semi-transparent polymer solar cells possessing tandem structures. Energy Environ. Sci. 6, 2714–2720 (2013).
Xu, G. et al. High-performance colorful semitransparent polymer solar cells with ultrathin hybrid-metal electrodes and fine-tuned dielectric mirrors. Adv. Funct. Mater. 27, 1605908 (2017).
Zhang, M., Guo, X., Ma, W., Ade, H. & Hou, J. A large-bandgap conjugated polymer for versatile photovoltaic applications with high performance. Adv. Mater. 27, 4655–4660 (2015).
Wang, W. et al. Fused hexacyclic nonfullerene acceptor with strong near-infrared absorption for semitransparent organic solar cells with 9.77% efficiency. Adv. Mater. 29, 1701308 (2017).
Green, M. A. Solar cell fill factors: general graph and empirical expressions. Solid State Electron. 24, 788 (1981).
Green, M. A., Emery, K., Hishikawa, Y., Warta, W. & Dunlop, E. D. Solar cell efficiency tables (version 47). Prog. Photovolt. Res. Appl. 24, 3–11 (2016).
Jao, M.-H., Liao, H.-C. & Su, W.-F. Achieving a high fill factor for organic solar cells. J. Mater. Chem. A 4, 5784–5801 (2016).
Li, S. et al. Design of a new small-molecule electron acceptor enables efficient polymer solar cells with high fill factor. Adv. Mater. 29, 1704051 (2017).
We thank Thomas Kirchartz for insightful discussions. The work was supported by the National Natural Science Foundation of China (grant nos 91633301, 91333204, 51673201, 21325419 and 51711530159), the Chinese Academy of Sciences (grant no. XDB12030200), the Swedish Research Council VR (grant nos 2017-00744 and 2016-06146), the Swedish Energy Agency Energimyndigheten (2016-010174), the Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linköping University (faculty grant no. SFO-Mat-LiU #2009-00971), the Engineering and Physical Sciences Research Council in the UK, and the Knut and Alice Wallenberg foundation (KAW) through a Wallenberg Scholar grant to O.I.
The authors declare no competing financial interests.
About this article
Cite this article
Hou, J., Inganäs, O., Friend, R. et al. Organic solar cells based on non-fullerene acceptors. Nat. Mater. 17, 119–128 (2018). https://doi.org/10.1038/nmat5063
This article is cited by
Rational design of dithieno[2,3-D:2ʹ,3ʹ-Dʹ]-benzo[1,2-B:4,5-Bʹ] dithiophene based small molecule donor for plausible performance organic solar cell
Optical and Quantum Electronics (2023)
Journal of the Korean Physical Society (2023)
Science China Chemistry (2023)
Nature Nanotechnology (2022)
Unraveling complex performance-limiting factors of brominated ITIC derivative: PM6 organic solar cells by using time-resolved measurements
Polymer Journal (2022)