The role of chemical design in the performance of organic semiconductors


Organic semiconductors are solution-processable, lightweight and flexible and are increasingly being used as the active layer in a wide range of new technologies. The versatility of synthetic organic chemistry enables the materials to be tuned such that they can be incorporated into biological sensors, wearable electronics, photovoltaics and flexible displays. These devices can be improved by improving their material components, not only by developing the synthetic chemistry but also by improving the analytical and computational techniques that enable us to understand the factors that govern material properties. Judicious molecular design provides control of the semiconductor frontier molecular orbital energy distribution and guides the hierarchical assembly of organic semiconductors into functional films where we can manipulate the properties and motion of charges and excited states. This Review describes how molecular design plays an integral role in developing organic semiconductors for electronic devices in present and emerging technologies.

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Fig. 1: Manipulating frontier orbital distributions and energies.
Fig. 2: Schematic illustrations and chemical structures of conjugated thiophene-derived polymers.
Fig. 3: Species that may find applications in organic field effect transistors.
Fig. 4: Donor:acceptor bulk heterojunctions and some typical semiconducting components.
Fig. 5: The evolution of molecular organic light emitters.


  1. 1.

    Holliday, S. et al. A rhodanine flanked nonfullerene acceptor for solution-processed organic photovoltaics. J. Am. Chem. Soc. 137, 898–904 (2015).

  2. 2.

    Planells, M., Schroeder, B. C. & McCulloch, I. Effect of chalcogen atom substitution on the optoelectronic properties in cyclopentadithiophene polymers. Macromolecules 47, 5889–5894 (2014).

  3. 3.

    Nikolka, M. et al. High operational and environmental stability of high-mobility conjugated polymer field-effect transistors through the use of molecular additives. Nat. Mater. 16, 356–362 (2016).

  4. 4.

    de Leeuw, D. M., Simenon, M. M. J., Brown, A. R. & Einerhand, R. E. F. Stability of n-type doped conducting polymers and consequences for polymeric microelectronic devices. Synth. Met. 87, 53–59 (1997).

  5. 5.

    Abbaszadeh, D. et al. Electron trapping in conjugated polymers. Chem. Mater. 31, 6380–6386 (2019).

  6. 6.

    Usta, H. et al. Design, synthesis, and characterization of ladder-type molecules and polymers. air-stable, solution-processable n-channel and ambipolar semiconductors for thin-film transistors via experiment and theory. J. Am. Chem. Soc. 131, 5586–5608 (2009).

  7. 7.

    McCulloch, I. et al. Liquid-crystalline semiconducting polymers with high charge-carrier mobility. Nat. Mater. 5, 328–333 (2006).

  8. 8.

    Lei, T. et al. Systematic investigation of isoindigo-based polymeric field-effect transistors: design strategy and impact of polymer symmetry and backbone curvature. Chem. Mater. 24, 1762–1770 (2012).

  9. 9.

    Venkateshvaran, D. et al. Approaching disorder-free transport in high-mobility conjugated polymers. Nature 515, 384–388 (2014).

  10. 10.

    Lemaur, V. et al. Resilience to conformational fluctuations controls energetic disorder in conjugated polymer materials: insights from atomistic simulations. Chem. Mater. 31, 6889–6899 (2019).

  11. 11.

    Nielsen, C. B., White, A. J. P. & McCulloch, I. Effect of fluorination of 2,1,3-benzothiadiazole. J. Org. Chem. 80, 5045–5048 (2015).

  12. 12.

    Conboy, G. et al. To bend or not to bend — are heteroatom interactions within conjugated molecules effective in dictating conformation and planarity? Mater. Horiz. 3, 333–339 (2016).

  13. 13.

    Thorley, K. J. & McCulloch, I. Why are S–F and S–O non-covalent interactions stabilising? J. Mater. Chem. C 6, 12413–12421 (2018).

  14. 14.

    von Eller-Pandraud, H. Structure cristalline de l’isoindigo. Acta Cryst. 13, 936–938 (1960).

  15. 15.

    Naik, M. A., Venkatramaiah, N., Kanimozhi, C. & Patil, S. Influence of side-chain on structural order and photophysical properties in thiophene based diketopyrrolopyrroles: a systematic study. J. Phys. Chem. C 116, 26128–26137 (2012).

  16. 16.

    Anthony, J. E., Brooks, J. S., Eaton, D. L. & Parkin, S. R. Functionalized pentacene:  improved electronic properties from control of solid-state order. J. Am. Chem. Soc. 123, 9482–9483 (2001).

  17. 17.

    Ebata, H. et al. Highly soluble [1]benzothieno[3,2-b]benzothiophene (BTBT) derivatives for high-performance, solution-processed organic field-effect transistors. J. Am. Chem. Soc. 129, 15732–15733 (2007).

  18. 18.

    Sariciftci, N. S., Smilowitz, L., Heeger, A. J. & Wudl, F. Photoinduced electron transfer from a conducting polymer to buckminsterfullerene. Science 258, 1474–1476 (1992).

  19. 19.

    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).

  20. 20.

    Tamai, Y., Ohkita, H., Benten, H. & Ito, S. Exciton diffusion in conjugated polymers: from fundamental understanding to improvement in photovoltaic conversion efficiency. J. Phys. Chem. Lett. 6, 3417–3428 (2015).

  21. 21.

    Kim, Y. et al. A strong regioregularity effect in self-organizing conjugated polymer films and high-efficiency polythiophene: fullerene solar cells. Nat. Mater. 5, 197–203 (2006).

  22. 22.

    Scharber, M. C. et al. Design rules for donors in bulk-heterojunction solar cells — towards 10 % energy-conversion efficiency. Adv. Mater. 18, 789–794 (2006).

  23. 23.

    Kirkpatrick, J. et al. A systematic approach to the design optimization of light-absorbing indenofluorene polymers for organic photovoltaics. Adv. Energy Mater. 2, 260–265 (2012).

  24. 24.

    Peet, J. et al. Efficiency enhancement in low-bandgap polymer solar cells by processing with alkane dithiols. Nat. Mater. 6, 497–500 (2007).

  25. 25.

    Liu, Y. et al. Aggregation and morphology control enables multiple cases of high-efficiency polymer solar cells. Nat. Commun. 5, 5293 (2014).

  26. 26.

    Dimitrov, S. D. et al. Towards optimisation of photocurrent from fullerene excitons in organic solar cells. Energy Environ. Sci. 7, 1037–1043 (2014).

  27. 27.

    Sun, Y. et al. Solution-processed small-molecule solar cells with 6.7% efficiency. Nat. Mater. 11, 44–48 (2011).

  28. 28.

    Li, W., Hendriks, K. H., Furlan, A., Wienk, M. M. & Janssen, R. A. High quantum efficiencies in polymer solar cells at energy losses below 0.6 eV. J. Am. Chem. Soc. 137, 2231–2234 (2015).

  29. 29.

    Meng, D. et al. High-performance solution-processed non-fullerene organic solar cells based on selenophene-containing perylene bisimide acceptor. J. Am. Chem. Soc. 138, 375–380 (2016).

  30. 30.

    Zhang, J. et al. Ring-fusion of perylene diimide acceptor enabling efficient nonfullerene organic solar cells with a small voltage loss. J. Am. Chem. Soc. 139, 16092–16095 (2017).

  31. 31.

    Holliday, S. et al. High-efficiency and air-stable P3HT-based polymer solar cells with a new non-fullerene acceptor. Nat. Commun. 7, 11585 (2016).

  32. 32.

    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).

  33. 33.

    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).

  34. 34.

    Lin, Y. et al. An electron acceptor challenging fullerenes for efficient polymer solar cells. Adv. Mater. 27, 1170–1174 (2015).

  35. 35.

    Zhao, W. et al. Molecular optimization enables over 13% efficiency in organic solar cells. J. Am. Chem. Soc. 139, 7148–7151 (2017).

  36. 36.

    Zhang, H. et al. Over 14% efficiency in organic solar cells enabled by chlorinated nonfullerene small-molecule acceptors. Adv. Mater. 30, 1800613 (2018).

  37. 37.

    Yuan, J. et al. Single-junction organic solar cell with over 15% efficiency using fused-ring acceptor with electron-deficient core. Joule 3, 1140–1151 (2019).

  38. 38.

    Cui, Y. et al. Over 16% efficiency organic photovoltaic cells enabled by a chlorinated acceptor with increased open-circuit voltages. Nat. Commun. 10, 2515 (2019).

  39. 39.

    Kim, K.-H. & Kim, J.-J. Origin and control of orientation of phosphorescent and TADF dyes for high-efficiency OLEDs. Adv. Mater. 30, 1705600 (2018).

  40. 40.

    Jurow, M. J. et al. Understanding and predicting the orientation of heteroleptic phosphors in organic light-emitting materials. Nat. Mater. 15, 85–91 (2015).

  41. 41.

    Schmidt, T. D. et al. Emitter orientation as a key parameter in organic light-emitting diodes. Phys. Rev. Appl. 8, 037001 (2017).

  42. 42.

    Moon, C.-K., Kim, K.-H. & Kim, J.-J. Unraveling the orientation of phosphors doped in organic semiconducting layers. Nat. Commun. 8, 791 (2017).

  43. 43.

    Lee, J. et al. Deep blue phosphorescent organic light-emitting diodes with very high brightness and efficiency. Nat. Mater. 15, 92–98 (2016).

  44. 44.

    Tuong, Ly,K. et al. Near-infrared organic light-emitting diodes with very high external quantum efficiency and radiance. Nat. Photonics 11, 63–68 (2016).

  45. 45.

    Uoyama, H., Goushi, K., Shizu, K., Nomura, H. & Adachi, C. Highly efficient organic light-emitting diodes from delayed fluorescence. Nature 492, 234–238 (2012).

  46. 46.

    Hirata, S. et al. Highly efficient blue electroluminescence based on thermally activated delayed fluorescence. Nat. Mater. 14, 330–336 (2014).

  47. 47.

    Zhang, Q. et al. Efficient blue organic light-emitting diodes employing thermally activated delayed fluorescence. Nat. Photonics 8, 326–332 (2014).

  48. 48.

    Lin, T.-A. et al. Sky-blue organic light emitting diode with 37% external quantum efficiency using thermally activated delayed fluorescence from spiroacridine–triazine hybrid. Adv. Mater. 28, 6976–6983 (2016).

  49. 49.

    Kaji, H. et al. Purely organic electroluminescent material realizing 100% conversion from electricity to light. Nat. Commun. 6, 8476 (2015).

  50. 50.

    Zeng, W. et al. Realizing 22.5% external quantum efficiency for solution-processed thermally activated delayed-fluorescence OLEDs with red emission at 622 nm via a synergistic strategy of molecular engineering and host selection. Adv. Mater. 31, 1901404 (2019).

  51. 51.

    Wong, M. Y. & Zysman-Colman, E. Purely organic thermally activated delayed fluorescence materials for organic light-emitting diodes. Adv. Mater. 29, 1605444 (2017).

  52. 52.

    Dias, F. B. et al. The role of local triplet excited states and D–A relative orientation in thermally activated delayed fluorescence: photophysics and devices. Adv. Sci. 3, 1600080 (2016).

  53. 53.

    Etherington, M. K., Gibson, J., Higginbotham, H. F., Penfold, T. J. & Monkman, A. P. Revealing the spin–vibronic coupling mechanism of thermally activated delayed fluorescence. Nat. Commun. 7, 13680 (2016).

  54. 54.

    Samanta, P. K., Kim, D., Coropceanu, V. & Brédas, J.-L. Up-conversion intersystem crossing rates in organic emitters for thermally activated delayed fluorescence: impact of the nature of singlet vs triplet excited states. J. Am. Chem. Soc. 139, 4042–4051 (2017).

  55. 55.

    Noda, H. et al. Critical role of intermediate electronic states for spin-flip processes in charge-transfer-type organic molecules with multiple donors and acceptors. Nat. Mater. 18, 1084–1090 (2019).

  56. 56.

    Nakanotani, H. et al. High-efficiency organic light-emitting diodes with fluorescent emitters. Nat. Commun. 5, 4016 (2014).

  57. 57.

    Pershin, A. et al. Highly emissive excitons with reduced exchange energy in thermally activated delayed fluorescent molecules. Nat. Commun. 10, 597 (2019).

  58. 58.

    Hatakeyama, T. et al. Ultrapure blue thermally activated delayed fluorescence molecules: efficient HOMO–LUMO separation by the multiple resonance effect. Adv. Mater. 28, 2777–2781 (2016).

  59. 59.

    Kondo, Y. et al. Narrowband deep-blue organic light-emitting diode featuring an organoboron-based emitter. Nat. Photonics 13, 678–682 (2019).

  60. 60.

    Di, D. et al. High-performance light-emitting diodes based on carbene-metal-amides. Science 356, 159–163 (2017).

  61. 61.

    Hamze, R. et al. Eliminating nonradiative decay in Cu(i) emitters: >99% quantum efficiency and microsecond lifetime. Science 363, 601–606 (2019).

  62. 62.

    Freeman, D. M. E. et al. Synthesis and exciton dynamics of donor-orthogonal acceptor conjugated polymers: reducing the singlet–triplet energy gap. J. Am. Chem. Soc. 139, 11073–11080 (2017).

  63. 63.

    Schweicher, G. et al. Chasing the ‘killer’ phonon mode for the rational design of low disorder, high mobility molecular semiconductors. Adv. Mater. 31, 1902407 (2019).

  64. 64.

    Rivnay, J. et al. Structural control of mixed ionic and electronic transport in conducting polymers. Nat. Commun. 7, 11287 (2016).

  65. 65.

    Someya, T., Bao, Z. & Malliaras, G. G. The rise of plastic bioelectronics. Nature 540, 379–385 (2016).

  66. 66.

    Giovannitti, A. et al. Controlling the mode of operation of organic transistors through side-chain engineering. Proc. Natl Acad. Sci. USA 113, 12017–12022 (2016).

  67. 67.

    Nielsen, C. B. et al. Molecular design of semiconducting polymers for high-performance organic electrochemical transistors. J. Am. Chem. Soc. 138, 10252–10259 (2016).

  68. 68.

    Giovannitti, A. et al. N-type organic electrochemical transistors with stability in water. Nat. Commun. 7, 13066 (2016).

  69. 69.

    Sun, H. et al. Complementary logic circuits based on high-performance n-type organic electrochemical transistors. Adv. Mater. 30, 1704916 (2018).

  70. 70.

    Yao, H. et al. 14.7% efficiency organic photovoltaic cells enabled by active materials with a large electrostatic potential difference. J. Am. Chem. Soc. 141, 7743–7750 (2019).

  71. 71.

    Peng, Q., Obolda, A., Zhang, M. & Li, F. Organic light-emitting diodes using a neutral π radical as emitter: the emission from a doublet. Angew. Chem. Int. Ed. 54, 7091–7095 (2015).

  72. 72.

    Ai, X. et al. Efficient radical-based light-emitting diodes with doublet emission. Nature 563, 536–540 (2018).

  73. 73.

    Nagata, R., Nakanotani, H., Potscavage, W. J. Jr. & Adachi, C. Exploiting singlet fission in organic light-emitting diodes. Adv. Mater. 30, 1801484 (2018).

  74. 74.

    Salehi, A. et al. Realization of high-efficiency fluorescent organic light-emitting diodes with low driving voltage. Nat. Commun. 10, 2305 (2019).

  75. 75.

    Kimura, K. et al. Selective triplet exciton formation in a single molecule. Nature 570, 210–213 (2019).

  76. 76.

    Di, D. et al. Efficient triplet exciton fusion in molecularly doped polymer light-emitting diodes. Adv. Mater. 29, 1605987 (2017).

  77. 77.

    Onwubiko, A. et al. Fused electron deficient semiconducting polymers for air stable electron transport. Nat. Commun. 9, 416 (2018).

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B.C.S. acknowledges the UK Research and Innovation for Future Leaders Fellowship MR/S031952/1 and the British Council 337323.

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All authors contributed equally to the preparation of this manuscript.

Correspondence to Iain McCulloch.

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Bronstein, H., Nielsen, C.B., Schroeder, B.C. et al. The role of chemical design in the performance of organic semiconductors. Nat Rev Chem 4, 66–77 (2020).

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