Bowl-Shaped Naphthalimide-Annulated Corannulene as Nonfullerene Acceptor in Organic Solar Cells

Abstract

An electron-poor bowl-shaped naphthalimide-annulated corannulene with branched alkyl residues in the imide position was synthesized by a palladium-catalyzed cross-coupling annulation sequence. This dipolar compound exhibits strong absorption in the visible range along with a low-lying LUMO level at –3.85 eV, enabling n-type charge transport in organic thin-film transistors. Furthermore, we processed inverted bulk-heterojunction solar cells in combination with the two donor polymers PCE–10 and PM6 to achieve open-circuit voltages up to 1.04 V. By using a blend of the self-assembled naphthalimide-annulated corannulene and PCE–10, we were able to obtain a power conversion efficiency of up to 2.1%, which is to the best of our knowledge the highest reported value for a corannulene-based organic solar cell to date.

Key words

corannulene - curved π-systems - bulk-heterojunction solar cells - nonfullerene acceptors - aggregation

• References

• 1 Ma Z, Winands T, Liang N, Meng D, Jiang W, Doltsinis NL, Wang Z. Sci. China Chem. 2020; 63: 208
• 2 Wang X.-Y, Yao X, Müllen K. Sci. China Chem. 2019; 62: 1099
• 3 Wu Y.-T, Siegel JS. Chem. Rev. 2006; 106: 4843
• 4 Duan C, Zango G, García Iglesias M, Colberts FJ.M, Wienk MM, Martínez-Díaz MV, Janssen RA.J, Torres T. Angew. Chem. Int. Ed. 2017; 56: 148
• 5 Magiera KM, Aryal V, Chalifoux WA. Org. Biomol. Chem. 2020; 18: 2372
• 6 Meng D, Liu G, Xiao C, Shi Y, Zhang L, Jiang L, Baldridge KK, Li Y, Siegel JS, Wang Z. J. Am. Chem. Soc. 2019; 141: 5402
• 7 Huang X, Hu M, Zhao X, Li C, Yuan Z, Liu X, Cai C, Zhang Y, Hu Y, Chen Y. Org. Lett. 2019; 21: 3382
• 8 Luo Z, Liu T, Cheng W, Wu K, Xie D, Huo L, Sun Y, Yang C. J. Mater. Chem. C 2018; 6: 1136
• 9 Hendsbee AD, Sun J.-P, Law WK, Yan H, Hill IG, Spasyuk DM, Welch GC. Chem. Mater. 2016; 28: 7098
• 10 Zhong Y, Trinh MT, Chen R, Purdum GE, Khlyabich PP, Sezen M, Oh S, Zhu H, Fowler B, Zhang B, Wang W, Nam CY, Sfeir MY, Black CT, Steigerwald ML, Loo YL, Ng F, Zhu XY, Nuckolls C. Nat. Commun. 2015; 6: 8242
• 11 Huang T, Chen H, Feng J, Zhang A, Jiang W, He F, Wang Z. ACS Mater. Lett. 2019; 1: 404
• 12 Verreet B, Rand BP, Cheyns D, Hadipour A, Aernouts T, Heremans P, Medina A, Claessens CG, Torres T. Adv. Energy Mater. 2011; 1: 565
• 13 Barth WE, Lawton RG. J. Am. Chem. Soc. 1966; 88: 380
• 14 Nestoros E, Stuparu MC. Chem. Commun. 2018; 54: 6503
• 15 Chen R, Lu R.-Q, Shi K, Wu F, Fang H.-X, Niu Z.-X, Yan X.-Y, Luo M, Wang X.-C, Yang C.-Y, Wang X.-Y, Xu B, Xia H, Pei J, Cao X.-Y. Chem. Commun. 2015; 51: 13768
• 16 Shi K, Lei T, Wang X.-Y, Wang J.-Y, Pei J. Chem. Sci. 2014; 5: 1041
• 17 Lu R.-Q, Zhou Y.-N, Yan X.-Y, Shi K, Zheng Y.-Q, Luo M, Wang X.-C, Pei J, Xia H, Zoppi L, Baldridge KK, Siegel JS, Cao X.-Y. Chem. Commun. 2015; 51: 1681
• 18 Mack J, Vogel P, Jones D, Kaval N, Sutton A. Org. Biomol. Chem. 2007; 5: 2448
• 19 Valenti G, Bruno C, Rapino S, Fiorani A, Jackson EA, Scott LT, Paolucci F, Marcaccio M. J. Phys. Chem. C 2010; 114: 19467
• 20 Li J, Terec A, Wang Y, Joshi H, Lu Y, Sun H, Stuparu MC. J. Am. Chem. Soc. 2017; 139: 3089
• 21 Anthony JE. Chem. Mater. 2011; 23: 583
• 22 Chen R, Lu R.-Q, Shi P.-C, Cao X.-Y. Chin. Chem. Lett. 2016; 27: 1175
• 23 Rajeshkumar V, Marc C, Fichou D, Stuparu MC. Synlett 2016; 27: 2101
• 24 Deng Y, Xu B, Castro E, Fernandez-Delgado O, Echegoyen L, Baldridge KK, Siegel JS. Eur. J. Org. Chem. 2017; 29: 4338
• 25 Lu RQ, Zheng YQ, Zhou YN, Yan XY, Lei T, Shi K, Zhou Y, Pei J, Zoppi L, Baldridge KK, Siegel JS, Cao XY. J. Mater. Chem. A 2014; 2: 20515
• 26 Shoyama K, Schmidt D, Mahl M, Würthner F. Org. Lett. 2017; 19: 5328
• 27 Renner R, Stolte M, Würthner F. ChemistryOpen 2019; 9: 32
• 28 Shoyama K, Würthner F. J. Am. Chem. Soc. 2019; 141: 13008
• 29 Gershberg J, Fennel F, Rehm TH, Lochbrunner S, Würthner F. Chem. Sci. 2016; 7: 1729
• 30 Cardona CM, Li W, Kaifer AE, Stockdale D, Bazan GC. Adv. Mater. 2011; 23: 2367
• 31 Organic solar cells were prepared by cleaning ITO substrates (Soluxx GmbH) with acetone (VWR, semiconductor grade), detergent, deionized water, and isopropanol (VWR, semiconductor grade) for 15 min each, followed by an ozone/UV treatment for 30 min. The ZnO layer was deposited by spin-coating ZnO nanoparticles on top of the substrates (3000 rpm, 30 s) followed by an annealing step (200 °C, 1 h). The donor–acceptor blends were prepared by stirring a 1:1 mixture with a total concentration of 15 mg mL⁻¹ of donor (PCE-10 obtained from 1-Material Inc.; PM6 obtained from Brilliant Matters Inc.) and 4 in chlorobenzene for 3 h at room temperature under inert conditions followed by spin-coating at 1000 rpm for 60 s (M. Braun Inertgas-Systeme GmbH, UNIlab Pro, c(O₂) < 1 ppm, c(H₂O) < 1 ppm). The substrates were placed in the evaporation system (OPTIvap-XL, Creaphys GmbH) and MoO₃ d = 10 nm, r = 0.1 Å s⁻¹, p < 10⁻⁶ mbar, rotation = 10 rpm) and aluminum (d = 100 nm, r = 1–2 Å s⁻¹, p < 10⁻⁶ mbar) were deposited on top of the active layer to obtain the inverted BHJ organic solar cells. The device area was 7.1 mm². J–V characteristics were measured after calibration with a standard silicon solar cell with a KG filter (ISE Freiburg) under an AM1.5G Oriel Sol3ATM Class AAA solar simulator (Newport^® ) by a parameter analyzer (Botest Systems GmbH). EQE measurements were carried out with a quantum efficiency/IPCE measurement kit (Newport^®) by using a 300 W Xe lamp and a Cornerstone monochromator with a Merlin lock-in amplifier for detection. Thin-film UV/Vis spectra were measured on a Jasco V770 spectrometer using an integration sphere. AFM images were obtained by an NT–MDT Next Solver system in semi-contact mode by using a SCOUT 350 RAI (Nu Nano Ltd) silicon cantilever (spring constant = 42 N m⁻¹ ; resonance frequency = 350 kHz).The high-resolution AFM image was measured at a AXS Multimode Nanoscope IV instrument in the tapping mode using a silicon cantilever from Olympus (OMCL-AC160TS) with a spring constant of 42 N m⁻¹ and a resonance frequency of 300 kHz
• 32 Organic thin film transistors were fabricated on wafer substrates based on Si/SiO₂(100 nm)/octadecyltriethoxysilane (OTES) with a capacitance of 32.4 nF cm⁻², which were rinsed prior to use with toluene (p.a. grade, VWR chemicals), acetone, and isopropanol (semiconductor grade, VLSI PURANAL™, Aldrich^® Chemistry), successively. After drying under nitrogen flow, the substrates were placed into a nitrogen-filled glovebox (M. Braun Inertgas-Systeme GmbH, UNIlab Pro, c(O₂) < 1 ppm, c(H₂O) < 1 ppm) and a freshly prepared solution of 4 (5 mg mL⁻¹ in chloroform) was spin-coated on top of the substrate (1000 rpm, 60 s) followed by an annealing step (100 °C, 5 Min). The substrates were placed into an evaporation system (OPTIvap-XL, Creaphys GmbH) and gold was deposited on top of the organic layer through a shadow mask (d = 30 nm, r = 0.2 Å s⁻¹, p < 10⁻⁶ mbar). The resulting transfer and output characteristics were measured under inert conditions with an Agilent 4055C parameter analyzer and a Cascade EPS150 probe station (W = 1000 μm, L = 20 μm)
• 33 Würthner F, Meerholz K. Chemistry 2010; 16: 9366