Vertical phase separation and morphology optimization of layer-by-layer non-fullerene organic solar cells

Abstract

The development of high-performance non-fullerene acceptors with extended exciton diffusion lengths has positioned the sequential layer-by-layer (LBL) solution processing technique as a promising approach for fabricating high-performance and large-area organic solar cells (OSCs). This method allows for the independent dissolution and deposition of donor and acceptor materials, enabling precise morphology control. In this review, we provide a comprehensive overview of the LBL processing technique, focusing on the morphology of the active layer. The swelling-intercalation phase-separation (SIPS) model is introduced as the mainstream theory of morphology evolution, with a detailed discussion on vertical phase separation. We summarize recent strategies for morphology optimization. Additionally, we review the progress in LBL-based large-area device and module fabrication, as well as green processing approaches. Finally, we highlight current challenges and future prospects, paving the way for the commercialization of LBL-processed OSCs.

References

[1] Chang J-h, Liu K, Lin S-y, et al.. Solution-processed perovskite solar cells [J]. Journal of Central South University, 2020, 27(4): 1104-1133.

[2] Bati A S R, Zhong Y l, Burn P L, et al.. Next-generation applications for integrated perovskite solar cells [J]. Communications Materials, 2023, 4: 2.

[3] Sharif R, Khalid A, Ahmad S W, et al.. A comprehensive review of the current progresses and material advances in perovskite solar cells [J]. Nanoscale Advances, 2023, 5(15): 3803-3833.

[4] Wang A, He M-r, Green M A, et al.. A critical review on the progress of kesterite solar cells: Current strategies and insights [J]. Advanced Energy Materials, 2023, 13(2): 2203046.

[5] Yao H-f, Hou J-hui. Recent advances in single-junction organic solar cells [J]. Angewandte Chemie (International Ed), 2022, 61(37): e202209021.

[6] Cao R, Chen Y, Cai F-f, et al.. A new chlorinated non-fullerene acceptor based organic photovoltaic cells over 12% efficiency [J]. Journal of Central South University, 2020, 27(12): 3581-3593.

[7] Li Z, Chen H-g, Yuan J, et al.. A new low-bandgap polymer acceptor based on benzotriazole for efficient all-polymer solar cells [J]. Journal of Central South University, 2021, 28(7): 1919-1931.

[8] Qin F, Wang W, Sun L-l, et al.. Robust metal ion-chelated polymer interfacial layer for ultraflexible non-fullerene organic solar cells [J]. Nature Communications, 2020, 11(1): 4508.

[9] Song W, Yu K-b, Zhou E-j, et al.. Crumple durable ultraflexible organic solar cells with an excellent power-per-weight performance [J]. Advanced Functional Materials, 2021, 31(30): 2102694.

[10] Yao M-n, Li T-f, Long Y-b, et al.. Color and transparency-switchable semitransparent polymer solar cells towards smart windows [J]. Science Bulletin, 2020, 65(3): 217-224.

[11] Li Y-x, Huang X-j, Sheriff H K M, et al.. Semitransparent organic photovoltaics for building-integrated photovoltaic applications [J]. Nature Reviews Materials, 2023, 8: 186-201.

[12] Zhang L, Yang F, Deng W, et al.. Organic-inorganic hybrid cathode interlayer for efficient flexible inverted organic solar modules [J]. Applied Physics Letters, 2023, 122(26): 263903.

[13] Tang C W. Two-layer organic photovoltaic cell [J]. Applied Physics Letters, 1986, 48(2): 183-185.

[14] Yu G, Gao J, Hummelen J C, et al.. Polymer photovoltaic cells: Enhanced efficiencies via a network of internal donor-acceptor heterojunctions [J]. Science, 1995, 270(5243): 1789-1791.

[15] Zhu L, Zhang M, Xu J-q, et al.. Single-junction organic solar cells with over 19% efficiency enabled by a refined double-fibril network morphology [J]. Nature Materials, 2022, 21(6): 656-663.

[16] Guo C-h, Sun Y-d, Wang L, et al.. Light-induced quinone conformation of polymer donors toward 19.9% efficiency organic solar cells [J]. Energy & Environmental Science, 2024, 17(7): 2492-2499.

[17] Sun Y-d, Wang L, Guo C-h, et al.. π-extended nonfullerene acceptor for compressed molecular packing in organic solar cells to achieve over 20% efficiency [J]. Journal of the American Chemical Society, 2024, 146(17): 12011-12019.

[18] Jiang Y-y, Sun S-m, Xu R-j, et al.. Non-fullerene acceptor with asymmetric structure and phenylsubstituted alkyl side chain for 20.2% efficiency organic solar cells [J]. Nature Energy, 2024, 9: 975-986.

[19] Baek W H, Yang H, Yoon T S, et al.. Effect of P3HT: PCBM concentration in solvent on performances of organic solar cells [J]. Solar Energy Materials and Solar Cells, 2009, 93(8): 1263-1267.

[20] Ho C H Y, Cheung S H, Li H W, et al.. Using ultralow dosages of electron acceptor to reveal the early stage donor-acceptor electronic interactions in bulk heterojunction blends [J]. Advanced Energy Materials, 2017, 7(12): 1602360.

[21] MCDOWELL C, ABDELSAMIE M, TONEY M F, et al. Solvent additives: Key morphology-directing agents for solution-processed organic solar cells [J]. Advanced Materials, 2018: e1707114. DOI: https://doi.org/10.1002/adma.201707114.

[22] Ye L, Zhao W-c, Li S-s, et al.. High-efficiency nonfullerene organic solar cells: Critical factors that affect complex multi-length scale morphology and device performance [J]. Advanced Energy Materials, 2017, 7(7): 1602000.

[23] Ayzner A L, Tassone C J, Tolbert S H, et al.. Reappraising the need for bulk heterojunctions in polymer-fullerene photovoltaics: The role of carrier transport in all-solution-processed P3HT/PCBM bilayer solar cells [J]. The Journal of Physical Chemistry C, 2009, 113(46): 20050-20060.

[24] Wang D H, Moon J S, Seifter J, et al.. Sequential processing: Control of nanomorphology in bulk heterojunction solar cells [J]. Nano Letters, 2011, 11(8): 3163-3168.

[25] Lee D H, Yang Y M, You J-b, et al.. Immiscible solvents enabled nanostructure formation for efficient polymer photovoltaic cells [J]. Nanotechnology, 2014, 25(29): 295401.

[26] Tao C, Aljada M, Shaw P E, et al.. Controlling hierarchy in solution-processed polymer solar cells based on crosslinked P3HT [J]. Advanced Energy Materials, 2013, 3(1): 105-112.

[27] Lee K H, Schwenn P E, Smith A R G, et al.. Morphology of all-solution-processed “bilayer” organic solar cells [J]. Advanced Materials, 2011, 23(6): 766-770.

[28] Chandrabose S, Chen K, Barker A J, et al.. High exciton diffusion coefficients in fused ring electron acceptor films [J]. Journal of the American Chemical Society, 2019, 141(17): 6922-6929.

[29] Firdaus Y, Le Corre V M, Karuthedath S, et al.. Long-range exciton diffusion in molecular non-fullerene acceptors [J]. Nature Communications, 2020, 11(1): 5220.

[30] Park S Y, Chandrabose S, Price M B, et al.. Photophysical pathways in efficient bilayer organic solar cells: The importance of interlayer energy transfer [J]. Nano Energy, 2021, 84: 105924.

[31] Wang J-y, Xie Y, Chen K, et al.. Physical insights into non-fullerene organic photovoltaics [J]. Nature Reviews Physics, 2024, 6: 365-381.

[32] Wei Y-n, Chen Z-h, Lu G-y, et al.. Binary organic solar cells breaking 19% via manipulating the vertical component distribution [J]. Advanced Materials, 2022, 34(33): e2204718.

[33] Xu X-p, Jing W-w, Meng H-f, et al.. Sequential deposition of multicomponent bulk heterojunctions increases efficiency of organic solar cells [J]. Advanced Materials, 2023, 35(12): e2208997.

[34] Luo S-w, Li C, Zhang J-q, et al.. Auxiliary sequential deposition enables 19%-efficiency organic solar cells processed from halogen-free solvents [J]. Nature Communications, 2023, 14(1): 6964.

[35] Zhou M-w, Liao C-t, Duan Y-w, et al.. 19.10% efficiency and 80.5% fill factor layer-by-layer organic solar cells realized by 4-bis(2-thienyl)P_yrrole-2, 5-dione based polymer additives for inducing vertical segregation morphology [J]. Advanced Materials, 2023, 35(35): 2208279.

[36] Ding G-y, Chen T-y, Wang M-t, et al.. Solid additive-assisted layer-by-layer processing for 19% efficiency binary organic solar cells [J]. Nano-micro Letters, 2023, 15(1): 92.

[37] Fu Z, Qiao J-w, Cui F-z, et al.. π-π stacking modulation via polymer adsorption for elongated exciton diffusion in high-efficiency thick-film organic solar cells [J]. Advanced Materials, 2024, 36(21): e2313532.

[38] Xie M-l, Zhu L-y, Zhang J-q, et al.. Effective N-doping of non-fullerene acceptor via sequential deposition enables high-efficiency organic solar cells [J]. Advanced Energy Materials, 2024, 14(24): 2400214.

[39] Lai S-t, Cui Y-j, Chen Z, et al.. Impact of electrostatic interaction on vertical morphology and energy loss in efficient pseudo-planar heterojunction organic solar cells [J]. Advanced Materials, 2024, 36(18): e2313105.

[40] Wang Y-f, Zhan X-wei. Layer-by-layer processed organic solar cells [J]. Advanced Energy Materials, 2016, 6(17): 1600414.

[41] Li X-r, Du X-y, Zhao J-w, et al.. Layer-by-layer solution processing method for organic solar cells [J]. Solar RRL, 2021, 5(1): 2000592.

[42] Yu R-n, Wei X-q, Wu G-z, et al.. Layer-by-layered organic solar cells: Morphology optimizing strategies and processing techniques [J]. Aggregate, 2022, 3(3): e107.

[43] Campoy-Quiles M, Ferenczi T, Agostinelli T, et al.. Morphology evolution via self-organization and lateral and vertical diffusion in polymer: Fullerene solar cell blends [J]. Nature Materials, 2008, 7(2): 158-164.

[44] Xu Z, Chen L-m, Yang G-w, et al.. Vertical phase separation in poly(3-hexylthiophene): Fullerene derivative blends and its advantage for inverted structure solar cells [J]. Advanced Functional Materials, 2009, 19(8): 1227-1234.

[45] Chen D, Liu F, Wang C, et al.. Bulk heterojunction photovoltaic active layers via bilayer interdiffusion [J]. Nano Letters, 2011, 11(5): 2071-2078.

[46] Kim D H, Mei J-g, Ayzner A L, et al.. Sequentially solution-processed, nanostructured polymer photovoltaics using selective solvents [J]. Energy & Environmental Science, 2014, 7(3): 1103-1109.

[47] Aguirre J C, Hawks S A, Ferreira A S, et al.. Sequential processing for organic photovoltaics: Design rules for morphology control by tailored semi-orthogonal solvent blends [J]. Advanced Energy Materials, 2015, 5(11): 1402020.

[48] van Franeker J J, Kouijzer S, Lou X-w, et al.. Depositing fullerenes in swollen polymer layers via sequential processing of organic solar cells [J]. Advanced Energy Materials, 2015, 5(14): 1500464.

[49] He C-l, Pan Y-w, Lu G-h, et al.. Versatile sequential casting processing for highly efficient and stable binary organic photovoltaics [J]. Advanced Materials, 2022, 34(33): e2203379.

[50] Qiu Y, Shi J-y, Peng R-x, et al.. Sequential deposition processing to control vertical composition distribution toward high-performance and stable inverted organic solar cells [J]. Advanced Optical Materials, 2024, 12(12): 2302548.

[51] Weng K-k, Ye L-l, Zhu L, et al.. Optimized active layer morphology toward efficient and polymer batch insensitive organic solar cells [J]. Nature Communications, 2020, 11(1): 2855.

[52] Wang Y-l, Xue J-w, Zhong H-y, et al.. Control of the crystallization and phase separation kinetics in sequential blade-coated organic solar cells by optimizing the upper layer processing solvent [J]. Advanced Energy Materials, 2023, 13(7): 2203496.

[53] van Franeker J J, Turbiez M, Li W-w, et al.. A real-time study of the benefits of co-solvents in polymer solar cell processing [J]. Nature Communications, 2015, 6: 6229.

[54] Xue J-w, Naveed H B, Zhao H, et al.. Kinetic processes of phase separation and aggregation behaviors in slot-die processed high efficiency Y6-based organic solar cells [J]. Journal of Materials Chemistry A, 2022, 10(25): 13439-13447.

[55] Yao Y, Hou J-h, Xu Z, et al.. Effects of solvent mixtures on the nanoscale phase separation in polymer solar cells [J]. Advanced Functional Materials, 2008, 18(12): 1783-1789.

[56] Zhan L-l, Li S-x, Xia X-x, et al.. Layer-by-layer processed ternary organic photovoltaics with efficiency over 18 [J]. Advanced Materials, 2021, 33(12): e2007231.

[57] Ma L-j, Yao H-f, Wang J-w, et al.. Impact of electrostatic interaction on bulk morphology in efficient donor-acceptor photovoltaic blends [J]. Angewandte Chemie (International Ed), 2021, 60(29): 15988-15994.

[58] Zhang Y, Wu B-q, He Y-k, et al.. Layer-by-layer processed binary all-polymer solar cells with efficiency over 16% enabled by finely optimized morphology [J]. Nano Energy, 2022, 93: 106858.

[59] Jin J-h, Wang Q, Shen W-f, et al.. High-efficiency ternary polymer solar cells with a gradient-blended structure fabricated by sequential deposition [J]. ACS Applied Materials & Interfaces, 2024, 16(12): 15121-15132.

[60] Chen H, Zhao T-x, Li L, et al.. 17.6% -efficient quasiplanar heterojunction organic solar cells from a chlorinated 3D network acceptor [J]. Advanced Materials, 2021, 33(37): e2102778.

[61] Fu H-t, Peng Z-x, Fan Q-p, et al.. A top-down strategy to engineer active layer morphology for highly efficient and stable all-polymer solar cells [J]. Advanced Materials, 2022, 34(33): e2202608.

[62] Liu Z-y, Zhang M, Zhang L, et al.. Over 19.1% efficiency for sequentially spin-coated polymer solar cells by employing ternary strategy [J]. Chemical Engineering Journal, 2023, 471: 144711.

[63] Feng K, Chen L-y, Cheng J-y, et al.. Understanding the composition of layer-by-layer deposited active layer at buried bottom surface [J]. Advanced Functional Materials, 2023, 33(21): 2214956.

[64] Yu S, Qin F, Dong X-y, et al.. Engineering an interfacial interaction to assist transfer printing of active layers for curved organic solar cells [J]. Organic Electronics, 2021, 93: 106162.

[65] Jiang K, Zhang J, Peng Z-x, et al.. Pseudo-bilayer architecture enables high-performance organic solar cells with enhanced exciton diffusion length [J]. Nature Communications, 2021, 12(1): 468.

[66] Lee J K, Ma W l, Brabec C J, et al.. Processing additives for improved efficiency from bulk heterojunction solar cells [J]. Journal of the American Chemical Society, 2008, 130(11): 3619-3623.

[67] Zhang L, Yang S-z, Ning B-c, et al.. Modulation of vertical component distribution for large-area thick-film organic solar cells [J]. Solar RRL, 2022, 6(1): 2100838.

[68] He X-j, Chan C C S, Kim J, et al.. 1-chloronaphthalene-induced donor/acceptor vertical distribution and carrier dynamics changes in nonfullerene organic solar cells and the governed mechanism [J]. Small Methods, 2022, 6(3): e2101475.

[69] Guo L-z, Li Q-d, Ren J-x, et al.. Halogenated thiophenes serve as solvent additives in mediating morphology and achieving efficient organic solar cells [J]. Energy & Environmental Science, 2022, 15(12): 5137-5148.

[70] Yang Q-q, Li X-t, Tang H, et al.. Ultrafast spectroscopic investigation of the effect of solvent additives on charge photogeneration and recombination dynamics in non-fullerene organic photovoltaic blends [J]. Journal of Materials Chemistry C, 2020, 8(20): 6724-6733.

[71] Zhang X, Wang H, Li D-h, et al.. Modulation of J-aggregation of nonfullerene acceptors toward near-infrared absorption and enhanced efficiency [J]. Macromolecules, 2020, 53(10): 3747-3755.

[72] Zhang Y, Liu K, Huang J-m, et al.. Graded bulk-heterojunction enables 17% binary organic solar cells via nonhalogenated open air coating [J]. Nature Communications, 2021, 12(1): 4815.

[73] He Q-n, Sheng W-p, Zhang M, et al.. Revealing morphology evolution in highly efficient bulk heterojunction and pseudo-planar heterojunction solar cells by additives treatment [J]. Advanced Energy Materials, 2021, 11(7): 2003390.

[74] Lee D-m, Park C, Ham G, et al.. Enhancement of vertical phase separation in sequentially deposited organic photovoltaics through the independent processing of additives [J]. Journal of Energy Chemistry, 2024, 94: 768-777.

[75] Li D-h, Deng N, Fu Y-w, et al.. Fibrillization of non-fullerene acceptors enables 19% efficiency pseudo-bulk heterojunction organic solar cells [J]. Advanced Materials, 2023, 35(6): e2208211.

[76] Zhu L-y, Zhang J-q, Guo Y, et al.. Small exciton binding energies enabling direct charge photogeneration towards low-driving-force organic solar cells [J]. Angewandte Chemie (International Ed), 2021, 60(28): 15348-15353.

[77] Wang X-k, Zhang L-f, Hu L, et al.. High-efficiency (16.93%) pseudo-planar heterojunction organic solar cells enabled by binary additives strategy [J]. Advanced Functional Materials, 2021, 31(33): 2102291.

[78] de Tremolet V B J, O’Hara K A, Ostrowski D P, et al.. Removal of residual diiodooctane improves photostability of high-performance organic solar cell polymers [J]. Chemistry of Materials, 2016, 28(3): 876-884.

[79] Wu W-w, Luo Y-m, Dela Peña T A, et al.. Defining solid additive’s pivotal role on morphology regulation in organic solar cells produced by layer-by-layer deposition [J]. Advanced Energy Materials, 2024, 14(22): 2400354.

[80] Fan B-b, Zhong W-k, Gao W, et al.. Understanding the role of removable solid additives: Selective interaction contributes to vertical component distributions [J]. Advanced Materials, 2023, 35(32): e2302861.

[81] Xiao M-j, Meng Y-d, Tang L-t, et al.. Solid additive-assisted selective optimization strategy for sequential deposited active layers to construct 19.16% efficiency binary organic solar cells [J]. Advanced Functional Materials, 2024, 34(13): 2311216.

[82] WANG Qian, ZHAO Shuo, DING Hao-jia, et al. Enhancing stability and performance of pseudo-planar heterojunction organic solar cells using a hindered phenolic antioxidant with over 19% efficiency [J]. Science China Materials, 2024: 1 - 12. DOI: https://doi.org/10.1007/s40843-024-3146-4.

[83] Gao J-h, Yu N, Chen Z-h, et al.. Over 19.2% efficiency of organic solar cells enabled by precisely tuning the charge transfer state via donor alloy strategy [J]. Advanced Science, 2022, 9(30): e2203606.

[84] Zuo L-j, Jo S B, Li Y-k, et al.. Dilution effect for highly efficient multiple-component organic solar cells [J]. Nature Nanotechnology, 2022, 17(1): 53-60.

[85] Xu X-p, Li Y, Peng Qiang. Ternary blend organic solar cells: Understanding the morphology from recent progress [J]. Advanced Materials, 2022, 34(46): e2107476.

[86] Liao X-f, Liu M-t, Pei H-q, et al.. Regulating crystallinity mismatch between donor and acceptor to improve exciton/charge transport in efficient organic solar cells [J]. Angewandte Chemie (International Ed), 2024, 63(11): e202318595.

[87] Zhou H, Zhang L, Ma X-l, et al.. Approaching 18% efficiency of ternary layer-by-layer polymer solar cells with alloyed acceptors [J]. Chemical Engineering Journal, 2023, 462: 142327.

[88] Liao X-f, Xie Q, Guo Y-x, et al.. Inhibiting excessive molecular aggregation to achieve highly efficient and stabilized organic solar cells by introducing a star-shaped nitrogen heterocyclic-ring acceptor [J]. Energy & Environmental Science, 2022, 15(1): 384-394.

[89] Chen X-y, Li Y-f, Jing W-w, et al.. Layer-by-layer organic solar cells enabled by 1, 3, 4-selenadiazole-containing crystalline small molecule with double-fibril network morphology [J]. Angewandte Chemie (International Ed), 2024, 63(21): e202402831.

[90] Zhang J-y, Mao H-d, Zhou K-k, et al.. Polymer-entangled spontaneous pseudo-planar heterojunction for constructing efficient flexible organic solar cells [J]. Advanced Materials, 2024, 36(7): e2309379.

[91] Zhang L, He Y-x, Deng W, et al.. High-efficiency flexible organic solar cells with a polymer-incorporated pseudo-planar heterojunction [J]. Discover Nano, 2024, 19(1): 39.

[92] Wang L, Chen C, Fu Y-w, et al.. Donor-acceptor mutually diluted heterojunctions for layer-by-layer fabrication of high-performance organic solar cells [J]. Nature Energy, 2024, 9: 208-218.

[93] Zhang H-r, Liu Y-q, Ran G-l, et al.. Sequentially processed bulk-heterojunction-buried structure for efficient organic solar cells with 500 nm thickness [J]. Advanced Materials, 2024, 36(25): 2400521.

[94] Tian H-y, Xu W-j, Liu Z-y, et al.. Over 18.8% efficiency of layer-by-layer organic photovoltaics enabled by ameliorating exciton utilization in acceptor layer [J]. Advanced Functional Materials, 2024, 34(16): 2313751.

[95] Wen L, Mao H-d, Zhang L-f, et al.. Achieving desired pseudo-planar heterojunction organic solar cells via binary-dilution strategy [J]. Advanced Materials, 2024, 36(3): e2308159.

[96] Han J-h, Xu H, Paleti S H K, et al.. Vertical stratification engineering of insulating Poly(aryl ether)s enables 18.6% organic solar cells with improved stability [J]. ACS Energy Letters, 2022, 7(9): 2927-2936.

[97] Zhang D-l, Wu Y, Yan C-q, et al.. Simultaneously improving stretchability and efficiency of flexible organic solar cells by incorporating a copolymer interlayer in active layer [J]. Advanced Functional Materials, 2024, 34(46): 2407681.

[98] Zhang L, Lin B-j, Ke Z-f, et al.. A universal approach to improve electron mobility without significant enlarging phase separation in IDT-based non-fullerene acceptor organic solar cells [J]. Nano Energy, 2017, 41: 609-617.

[99] Zeng R, Zhu L, Zhang M, et al.. All-polymer organic solar cells with nano-to-micron hierarchical morphology and large light receiving angle [J]. Nature Communications, 2023, 14(1): 4148.

[100] Li S-f, Shi C-z, Gong Y-x, et al.. Additivefree all-green solvent-processed efficient and stable pseudo-bilayer bulk heterojunction ternary organic solar cells [J]. The Journal of Physical Chemistry C, 2023, 127(40): 19918-19926.

[101] Xie Y-c, Zhou C-y, Ma X-l, et al.. High-reproducibility layer-by-layer non-fullerene organic photovoltaics with 19.18% efficiency enabled by vacuum-assisted molecular drift treatment [J]. Advanced Energy Materials, 2024, 14(11): 2400013.

[102] Li S-f, Shi C-z, Luo X-y, et al.. High-efficiency binary organic solar cells enabled by pseudo-bilayer configuration in dilute solution [J]. Solar RRL, 2023, 7(9): 2201090.

[103] Dong S, Zhang K, Xie B-m, et al.. High-performance large-area organic solar cells enabled by sequential bilayer processing via nonhalogenated solvents [J]. Advanced Energy Materials, 2019, 9(1): 1802832.

[104] Gu X-d, Shaw L, Gu K, et al.. The meniscus-guided deposition of semiconducting polymers [J]. Nature Communications, 2018, 9(1): 534.

[105] Sun R, Guo J, Sun C-k, et al.. A universal layer-by-layer solution-processing approach for efficient non-fullerene organic solar cells [J]. Energy & Environmental Science, 2019, 12(1): 384-395.

[106] Yang Y, Feng E-m, Li H-y, et al.. Layer-by-layer slot-die coated high-efficiency organic solar cells processed using twin boiling point solvents under ambient condition [J]. Nano Research, 2021, 14(11): 4236-4242.

[107] Sun R, Wu Q, Guo J, et al.. A layer-by-layer architecture for printable organic solar cells overcoming the scaling lag of module efficiency [J]. Joule, 2020, 4(2): 407-419.

[108] Sun R, Wang T, Yang X-r, et al.. High-speed sequential deposition of photoactive layers for organic solar cell manufacturing [J]. Nature Energy, 2022, 7: 1087-1099.

[109] Zhao H, Naveed H B, Lin B-j, et al.. Hot hydrocarbon-solvent slot-die coating enables high-efficiency organic solar cells with temperature-dependent aggregation behavior [J]. Advanced Materials, 2020, 32(39): e2002302.

[110] Zhang L, Guo X-l, Deng W, et al.. Regulating pre-aggregation in non-halogenated solvent to enhance the efficiency of organic solar cells [J]. Applied Physics Letters, 2024, 124(1): 013902.

[111] Zhang B, Chen W-j, Chen H-y, et al.. Rapid solidification for green-solvent-processed large-area organic solar modules with >16% efficiency [J]. Energy & Environmental Science, 2024, 17(8): 2935-2944.

[112] Wang P, Zhang J-y, Luo D, et al.. A pseudo planar heterojunction structure for eco-friendly printable organic solar cells achieving 19.05% efficiency [J]. Advanced Functional Materials, 2024, 34(38): 2402680.

[113] Zhang G-p, Zhao C-y, Zhu L-x, et al.. Toluene processed all-polymer solar cells with 18% efficiency and enhanced stability enabled by solid additive: Comparison between sequential-processing and blendcasting [J]. Energy & Environmental Materials, 2024, 7(4): 12683.

[114] LIU Ze-kun, FU Ying-ying, WU Jiang, et al. Removable additive assists blade-coated large-area organic solar cell modules fabricated with non-halogenated solvents achieving efficiency over 16% [J]. Advanced Functional Materials, 2024: 2401558. DOI: https://doi.org/10.1002/adfm.202401558.

[115] Xie C, Liang S-q, Zhang G-y, et al.. Water-processed organic solar cell with efficiency exceeding 11 [J]. Polymers, 2022, 14(19): 4229.

[116] Laval H, Holmes A, Marcus M A, et al.. Toward high efficiency water processed organic photovoltaics: Controlling the nanoparticle morphology with surface energies [J]. Advanced Energy Materials, 2023, 13(26): 2300249.

[117] Holmes A, Laval H, Guizzardi M, et al.. Water-based solar cells over 10% efficiency: Designing soft nanoparticles for improved processability [J]. Energy & Environmental Science, 2024, 17(3): 1107-1116.

[118] Xie C, Zeng X-h, Li C-s, et al.. Water-based layer-by-layer processing enables 19% efficient binary organic solar cells with minimized thickness sensitivity [J]. Energy & Environmental Science, 2024, 17(7): 2441-2452.

RIGHTS & PERMISSIONS

Central South University