Directly Cross-Linked Conjugated Polymer Donor Enables Efficient Polymer Solar Cells with Extraordinary Mechanical Robustness.

A cross-linking strategy can result in a three-dimensional network of interconnected chains for the copolymers, thereby improving their mechanical performance. In this work, a series of cross-linked conjugated copolymers, named PC2, PC5, and PC8, constructed with different ratios of monomers are designed and synthesized. For comparison, a random linear copolymer, PR2 is also synthesized based on the similar monomers. When blended with Y6 acceptor, the cross-linked polymers PC2, PC5, and PC8-based polymer solar cells (PSCs) achieve superior power conversion efficiencies (PCEs) of 17.58%, 17.02%, and 16.12%, respectively, which are higher than that (15.84%) of the random copolymer PR2-based devices. Moreover, the PCE of PC2:Y6-based flexible PSC retains ≈88% of the initial efficiency value after 2000 bending cycles, overwhelming the PR2:Y6-based device with the remaining 12.8% of the initial PCE. These results demonstrate that the cross-linking strategy is a feasible and facile approach to developing high-performance polymer donors for the fabrication of flexible PSCs.

[1]  Ruipeng Li,et al.  Benzo[d]thiazole Based Wide Bandgap Donor Polymers Enable 19.54% Efficiency Organic Solar Cells Along with Desirable Batch‐to‐Batch Reproducibility and General Applicability , 2023, Advanced materials.

[2]  Jianqi Zhang,et al.  Enhancing Photon Utilization Efficiency for High‐Performance Organic Photovoltaic Cells via Regulating Phase‐Transition Kinetics , 2023, Advanced materials.

[3]  W. Shen,et al.  Recent Developments of Polymer Solar Cells with Photovoltaic Performance over 17% , 2023, Advanced Functional Materials.

[4]  Dongyan Li,et al.  A Multifluorination Strategy Toward Wide Bandgap Polymers for Highly Efficient Organic Solar Cells. , 2023, Angewandte Chemie.

[5]  Ruijie Ma,et al.  Multifunctional all‐polymer photovoltaic blend with simultaneously improved efficiency (18.04%), stability and mechanical durability , 2022, Aggregate.

[6]  J. Min,et al.  A Versatile and Low‐Cost Polymer Donor Based on 4‐Chlorothiazole for Highly Efficient Polymer Solar Cells , 2022, Advanced materials.

[7]  C. Brabec,et al.  Renewed Prospects for Organic Photovoltaics. , 2022, Chemical reviews.

[8]  Yanming Sun,et al.  Revisiting Conjugated Polymers with Long-Branched Alkyl Chains: High Molecular Weight, Excellent Mechanical Properties, and Low Voltage Losses , 2022, Macromolecules.

[9]  Bumjoon J. Kim,et al.  Material Design and Device Fabrication Strategies for Stretchable Organic Solar Cells , 2022, Advanced materials.

[10]  Yongsheng Chen,et al.  Recent progress in organic solar cells (Part II device engineering) , 2022, Science China Chemistry.

[11]  Yongsheng Chen,et al.  Recent progress in organic solar cells (Part I material science) , 2021, Science China Chemistry.

[12]  Young Un Kim,et al.  Improved Stability of All-Polymer Solar Cells Using Crosslinkable Donor and Acceptor Polymers Bearing Vinyl Moieties in the Side-Chains. , 2021, ACS applied materials & interfaces.

[13]  Jianqi Zhang,et al.  On the understanding of energy loss and device fill factor trade-offs in non-fullerene organic solar cells with varied energy levels , 2020 .

[14]  D. Lipomi,et al.  Beyond Stretchability: Strength, Toughness, and Elastic Range in Semiconducting Polymers , 2020 .

[15]  Shangfeng Yang,et al.  18% Efficiency organic solar cells. , 2020, Science bulletin.

[16]  T. Park,et al.  Study of Burn‐In Loss in Green Solvent‐Processed Ternary Blended Organic Photovoltaics Derived from UV‐Crosslinkable Semiconducting Polymers and Nonfullerene Acceptors , 2019, Advanced Energy Materials.

[17]  Yanming Sun,et al.  Optimal bulk-heterojunction morphology enabled by fibril network strategy for high-performance organic solar cells , 2019, Science China Chemistry.

[18]  C. Li,et al.  Insertion of chlorine atoms onto π-bridges of conjugated polymer enables improved photovoltaic performance , 2019, Nano Energy.

[19]  Yanming Sun,et al.  Polymer Donors for High-Performance Non-Fullerene Organic Solar Cells. , 2019, Angewandte Chemie.

[20]  Fan Yang,et al.  Boosting the Performance of Non-Fullerene Organic Solar Cells via Cross-Linked Donor Polymers Design , 2019, Macromolecules.

[21]  He Yan,et al.  Aggregation and morphology control enables multiple cases of high-efficiency polymer solar cells , 2014, Nature Communications.

[22]  W. Su,et al.  Bi-hierarchical nanostructures of donor–acceptor copolymer and fullerene for high efficient bulk heterojunction solar cells , 2013 .

[23]  Alan J. Heeger,et al.  Intensity dependence of current-voltage characteristics and recombination in high-efficiency solution-processed small-molecule solar cells. , 2013, ACS nano.

[24]  Bumjoon J. Kim,et al.  Effects of Solubilizing Group Modification in Fullerene Bis-Adducts on Normal and Inverted Type Polymer Solar Cells , 2012 .

[25]  E. Moons,et al.  Morphology and Phase Segregation of Spin-Casted Films of Polyfluorene/PCBM Blends , 2007 .

[26]  Valentin D. Mihailetchi,et al.  Device Physics of Polymer:Fullerene Bulk Heterojunction Solar Cells , 2007 .

[27]  Junsheng Yu,et al.  High Electron Mobility in Room‐Temperature Discotic Liquid‐Crystalline Perylene Diimides , 2005 .