Developing novel unfused building blocks with simple synthesis and low cost is essential to advance and enrich cost-effective poly-mer donors;however,it remains a challenge due to the lack of efficient molecular strat...Developing novel unfused building blocks with simple synthesis and low cost is essential to advance and enrich cost-effective poly-mer donors;however,it remains a challenge due to the lack of efficient molecular strategies.Herein,a class of low-cost and fully unfused polymer donors with precisely regulated backbone planarity via halogenation was designed and synthesized,namely PDTBTBz-2H,PDTBTBz-2F,and PDTBTBz-2Cl.These polymer donors possess a four-step synthesis route with over 80%yield from cheap raw chemicals comparable to existing low-cost polymer donors,such as PTQ10.Benefitting from the planar backbone via in-corporating the F…S non-covalent interactions,PDTBTBz-2F exhibits more robust J-type aggregation in solution and a long-ranged molecular stacking in film relative to PDTBTBz-2H and PDTBTBz-2Cl.Moreover,the systematical study of PDTBTBz-based organic so-lar cells(OSCs)reveals the close relationship between optimized molecular self-assembly and charge separation/transport regarding backbone halogenation when paired with the non-fullerene acceptor(Y6-BO-4F).As a result,the photovoltaic devices based on semicrystalline PDTBTBz-2F achieved a promising power conversion efficiency(PCE)of 12.37%.Our work highlighted the influence of backbone halogenation on the molecular self-assembly properties and a potential unfused backbone motif for further developing cost-effective OSCs.展开更多
Single-ion conducting polymer electrolytes(SIPEs)are promising candidates for high-energy and highsafety lithium-metal batteries(LMBs).However,their insufficient ionic conductivity and electrochemical stability hinder...Single-ion conducting polymer electrolytes(SIPEs)are promising candidates for high-energy and highsafety lithium-metal batteries(LMBs).However,their insufficient ionic conductivity and electrochemical stability hinder their practical application.Herein,three new SIPEs,i.e.,poly(1,4-phenylene ether ether sulfone)-Li(PEES-Li),polysulfone-Li(PSF-Li),and hexafluoropolysulfone-Li(6FPSF-Li),all containing covalently tethered perfluorinated ionic side chains,have been designed,synthesized,and compared to investigate the influence of the backbone chemistry and the concentration of the ionic group on their electrochemical properties and cell performance.Especially,the trifluoromethyl group in the backbone and the concentration of the ionic function appear to play an essential role for the charge transport and stability towards oxidation,and the combination of both yields the best-performing SIPE with high ionic conductivity of ca.2.5×10^(-4)S cm^(-1),anodic stability of more than 4.8 V,and the by far highest capacity retention in Li‖LiNi0.6Co0.2Mn0.2O2cells.展开更多
Despite the significant progress made recently in all-polymer solar cells(all-PSCs),it is still quite challenging to achieve high open-circuit voltage(V_(oc))and short-circuit current density(J_(sc))simultaneously in ...Despite the significant progress made recently in all-polymer solar cells(all-PSCs),it is still quite challenging to achieve high open-circuit voltage(V_(oc))and short-circuit current density(J_(sc))simultaneously in order to further improve their performance.The recent strategy of using selenophene to replace thiophene on the Y6 based polymer acceptors has resulted in significantly improved J_(sc)s of the resulting all-PSCs.However,such modifications have also depressed V_(oc),which compromises the overall performance of the devices.Herein,we present the design and synthesis of a novel polymer acceptor,PYT-1S1Se,created by inserting an asymmetrical selenophene-fused framework to precisely manipulate optical absorption and electronic properties.Compared with the selenium-free analog,PYT-2S,and symmetrical selenium-fused analog,PYT-2Se,the PYT-1S1Se derived all-PSCs not only deliver optimized J_(sc)(24.1 mA cm^(−2))and V_(oc)(0.926 V)metrics,but also exhibit a relatively low energy loss of 0.502 eV.Consequently,these devices obtain a record-high power conversion efficiency(PCE)of 16.3%in binary all-PSCs.This work demonstrates an effective molecular design strategy for balancing the trade-off between V_(oc) and J_(sc) to achieve highefficiency all-PSCs.展开更多
By introducing various low concentrations of Iridium complexes to the famous donor polymer of PTB7-Th backbone,new heavy metal containing terpolymers have been demonstrated.When blended with PC71BM,an obvious increase...By introducing various low concentrations of Iridium complexes to the famous donor polymer of PTB7-Th backbone,new heavy metal containing terpolymers have been demonstrated.When blended with PC71BM,an obvious increase of power conversion efficiency(PCE)is obtained in 1 mol%Ir containing polymer for different photovoltaic devices either using Ca or PDIN as cathode interface layers.The impact of molecular weight on the photovoltaic performance has been particularly considered by using three batches of control polymer PTB7-Th to ensure a fair and more convincing comparison.At similar molecular weight conditions(Mn:~60 kg mol−1,M_(w):100-110 kg mol^(−1)),the 1 mol%Ir containing PTB7-ThIr1/PC71BM blends exhibits enhanced PCE to 9.19%compared with 7.92%of the control PTB7-Th.Through a combination of physical measurement,such as optoelectrical characterization,GIWAXS and pico-second time-resolved photoluminescence,the enhancement are contributed from comprehensive factors of higher hole mobility,less bimolecular recombination and more efficient slow process of charge separation.展开更多
基金supported by the National Natural Science Foundation of China (52203241,21905225,22005121)the Science and Technology Program of Shaanxi Province (2022JM-229,2023-JC-QN-0448)+1 种基金Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices,Soochow University (KJS2208)H.Y.W.acknowledges the financial support from the National Research Foundation of Korea (2019R1A6A1A11044070,2020M3H4A3081814).
文摘Developing novel unfused building blocks with simple synthesis and low cost is essential to advance and enrich cost-effective poly-mer donors;however,it remains a challenge due to the lack of efficient molecular strategies.Herein,a class of low-cost and fully unfused polymer donors with precisely regulated backbone planarity via halogenation was designed and synthesized,namely PDTBTBz-2H,PDTBTBz-2F,and PDTBTBz-2Cl.These polymer donors possess a four-step synthesis route with over 80%yield from cheap raw chemicals comparable to existing low-cost polymer donors,such as PTQ10.Benefitting from the planar backbone via in-corporating the F…S non-covalent interactions,PDTBTBz-2F exhibits more robust J-type aggregation in solution and a long-ranged molecular stacking in film relative to PDTBTBz-2H and PDTBTBz-2Cl.Moreover,the systematical study of PDTBTBz-based organic so-lar cells(OSCs)reveals the close relationship between optimized molecular self-assembly and charge separation/transport regarding backbone halogenation when paired with the non-fullerene acceptor(Y6-BO-4F).As a result,the photovoltaic devices based on semicrystalline PDTBTBz-2F achieved a promising power conversion efficiency(PCE)of 12.37%.Our work highlighted the influence of backbone halogenation on the molecular self-assembly properties and a potential unfused backbone motif for further developing cost-effective OSCs.
基金the financial support from the Federal Ministry of Education and Research(BMBF)within the Fest Batt project(03XP0175B)the FB2-Poly project(03XP0429B)the financial support from the Helmholtz Association。
文摘Single-ion conducting polymer electrolytes(SIPEs)are promising candidates for high-energy and highsafety lithium-metal batteries(LMBs).However,their insufficient ionic conductivity and electrochemical stability hinder their practical application.Herein,three new SIPEs,i.e.,poly(1,4-phenylene ether ether sulfone)-Li(PEES-Li),polysulfone-Li(PSF-Li),and hexafluoropolysulfone-Li(6FPSF-Li),all containing covalently tethered perfluorinated ionic side chains,have been designed,synthesized,and compared to investigate the influence of the backbone chemistry and the concentration of the ionic group on their electrochemical properties and cell performance.Especially,the trifluoromethyl group in the backbone and the concentration of the ionic function appear to play an essential role for the charge transport and stability towards oxidation,and the combination of both yields the best-performing SIPE with high ionic conductivity of ca.2.5×10^(-4)S cm^(-1),anodic stability of more than 4.8 V,and the by far highest capacity retention in Li‖LiNi0.6Co0.2Mn0.2O2cells.
基金supported by the APRC Grant of the City University of Hong Kong(9380086)Innovation and Technology Fund(ITS/497/18FP,GHP/021/18SZ)+7 种基金the Office of Naval Research(N00014-201-2191)the GRF grant(11307621)from the Research Grants Council of Hong Kongthe National Natural Science Foundation of China(21905103)the Natural Science Foundation of Guangdong Province(2019A1515010761,2019A1515011131)Guangdong Major Project of Basic and Applied Basic Research(2019B030302007)Guangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional Materials(2019B121205002)the Fundamental Research(Discipline Arrangement)Project funding from the Shenzhen Science and Technology Innovation Committee(JCYJ20180507181718203)US Office of Naval Research Contract N0001420-1-2116 for support。
文摘Despite the significant progress made recently in all-polymer solar cells(all-PSCs),it is still quite challenging to achieve high open-circuit voltage(V_(oc))and short-circuit current density(J_(sc))simultaneously in order to further improve their performance.The recent strategy of using selenophene to replace thiophene on the Y6 based polymer acceptors has resulted in significantly improved J_(sc)s of the resulting all-PSCs.However,such modifications have also depressed V_(oc),which compromises the overall performance of the devices.Herein,we present the design and synthesis of a novel polymer acceptor,PYT-1S1Se,created by inserting an asymmetrical selenophene-fused framework to precisely manipulate optical absorption and electronic properties.Compared with the selenium-free analog,PYT-2S,and symmetrical selenium-fused analog,PYT-2Se,the PYT-1S1Se derived all-PSCs not only deliver optimized J_(sc)(24.1 mA cm^(−2))and V_(oc)(0.926 V)metrics,but also exhibit a relatively low energy loss of 0.502 eV.Consequently,these devices obtain a record-high power conversion efficiency(PCE)of 16.3%in binary all-PSCs.This work demonstrates an effective molecular design strategy for balancing the trade-off between V_(oc) and J_(sc) to achieve highefficiency all-PSCs.
基金Research Program between China and European Union(2016YFE0112000)the Natural Science Foundation of Jiangsu Province(BK20160042)for financial support.
文摘By introducing various low concentrations of Iridium complexes to the famous donor polymer of PTB7-Th backbone,new heavy metal containing terpolymers have been demonstrated.When blended with PC71BM,an obvious increase of power conversion efficiency(PCE)is obtained in 1 mol%Ir containing polymer for different photovoltaic devices either using Ca or PDIN as cathode interface layers.The impact of molecular weight on the photovoltaic performance has been particularly considered by using three batches of control polymer PTB7-Th to ensure a fair and more convincing comparison.At similar molecular weight conditions(Mn:~60 kg mol−1,M_(w):100-110 kg mol^(−1)),the 1 mol%Ir containing PTB7-ThIr1/PC71BM blends exhibits enhanced PCE to 9.19%compared with 7.92%of the control PTB7-Th.Through a combination of physical measurement,such as optoelectrical characterization,GIWAXS and pico-second time-resolved photoluminescence,the enhancement are contributed from comprehensive factors of higher hole mobility,less bimolecular recombination and more efficient slow process of charge separation.
