Organic solar cells(OSCs) have drawn considerable attention in the last decade due to the great potential of light weight,flexibility, and low-cost solution processing. Particularly, Y-series non-fullerene acceptors(N...Organic solar cells(OSCs) have drawn considerable attention in the last decade due to the great potential of light weight,flexibility, and low-cost solution processing. Particularly, Y-series non-fullerene acceptors(NFAs) including small molecular acceptors(SMAs) and polymerized small molecular acceptors(PSMAs) have become research hot spots due to their excellent power conversion efficiency. Side chain engineering is crucial to adjust the solubility and crystallinity of NFAs, which will significantly affect the morphology of active layers and the efficiency of OSCs. However, the understanding of side chain engineering on NFAs is still limited and lacks a systematic review. This review aims to provide a brief summary of the recent developments in side chain engineering of NFAs, with a special focus on the design and application of Y-series SMAs and PSMAs for high-efficiency non-fullerene organic solar cells(NF-OSCs). In addition, the review also points out challenges and provides useful guidance regarding side chain regulation for Y-series NFAs.展开更多
Nonfullerene acceptors(NFAs),which usually possess symmetric skeletons,have drawn great attention in recent years due to their pronounced advantages over the fullerene counterparts.Moreover,breaking the symmetry of NF...Nonfullerene acceptors(NFAs),which usually possess symmetric skeletons,have drawn great attention in recent years due to their pronounced advantages over the fullerene counterparts.Moreover,breaking the symmetry of NFAs could fine tune the molecular dipole,solubility,energy level,intermolecular interaction,molecular packing,crystallinity,etc.,and give rise to improved photovoltaic performance.Currently,there are three main strategies for the design of asymmetric NFAs.This review highlights the recent advances of high-performance asymmetric NFAs and briefly outlooks the materials exploration for the future.展开更多
The power conversion efficiencies(PCEs)of single-junction organic solar cells(OSCs)have surpassed 19%,owing to the emerging Y-series nonfullerene acceptors(NFAs).Undoubtedly,the power and flexibility of chemical desig...The power conversion efficiencies(PCEs)of single-junction organic solar cells(OSCs)have surpassed 19%,owing to the emerging Y-series nonfullerene acceptors(NFAs).Undoubtedly,the power and flexibility of chemical design has been a strong driver for this rapid efficiency improvement in the OSC field.Over the course of the past 3 years,a variety of modifications have been made to the structure of the Y6 acceptor,and a large number of Y-series NFAs have been reported to further improve performance.Herein,we present our insights into the rationale behind the Y6 acceptor and discuss the design principles toward high-performance Y-series NFAs.It is clear that structural modifications through choice of heteroatom,soluble chains,πspacers,central cores,and end groups alter the material characteristics and properties,contributing to distinctive photovoltaic performance.Subsequently,we analyze various design strategies of Y-series-containing materials,including polymerized small-molecule acceptors(PSMA),non-fused-ring acceptors(NFRA),and all-fused-ring acceptors(AFRA).This review is expected to be of value in providing effective molecular design strategies for high-performance NFAs in future innovations.展开更多
The performance of organic solar cells(OSCs)is mainly related to the bulk heterojunction(BHJ)microstructure of specific active layer systems,which is often in a metastable state.A promising strategy to address the abo...The performance of organic solar cells(OSCs)is mainly related to the bulk heterojunction(BHJ)microstructure of specific active layer systems,which is often in a metastable state.A promising strategy to address the abovementioned shortcomings of BHJs is to develop single-component active layer materials.Owing to the single-component small molecule materials with defined chemical structures generally exhibit poor absorption spectra,herein we first introduced narrow bandgap Y-series acceptors into the molecular skeleton of single-component materials,and designed two molecular dyads,SM-Et-1Y and SM-Et-2Y.The optical bandgaps(E_g~(opt)s)of the two dyads are 1.364 and 1.361 eV,respectively,which are much smaller than those of previously reported single-component molecules.Consequently,the SM-Et-2Y-based single-component OSCs(SCOSCs)showed a power conversion efficiency(PCE)of 5.07%,superior to SM-Et-1Y(2.53%),which is one of the highest PCEs reported for SCOSCs to date.Moreover,both SM-Et-1Y-and SM-Et-2Y-based devices exhibited excellent photo-stability,retaining over 90%of their initial performance after 250 h of continuous illumination.Our results provide a deeper understanding of the molecular backbone and a guiding principle for the rational design or selection of non-fullerene single-component materials with suitable donor/acceptor ratios.展开更多
基金supported by the Science Foundation of Henan University of Technology(2021BS044)。
文摘Organic solar cells(OSCs) have drawn considerable attention in the last decade due to the great potential of light weight,flexibility, and low-cost solution processing. Particularly, Y-series non-fullerene acceptors(NFAs) including small molecular acceptors(SMAs) and polymerized small molecular acceptors(PSMAs) have become research hot spots due to their excellent power conversion efficiency. Side chain engineering is crucial to adjust the solubility and crystallinity of NFAs, which will significantly affect the morphology of active layers and the efficiency of OSCs. However, the understanding of side chain engineering on NFAs is still limited and lacks a systematic review. This review aims to provide a brief summary of the recent developments in side chain engineering of NFAs, with a special focus on the design and application of Y-series SMAs and PSMAs for high-efficiency non-fullerene organic solar cells(NF-OSCs). In addition, the review also points out challenges and provides useful guidance regarding side chain regulation for Y-series NFAs.
基金supported by the National Natural Science Foundation of China(Nos.22075069,51933001)Natural Science Foundation of Henan Province(No.212300410002)Program sponsored by Henan Province(Nos.23ZX002,ZYQR201912163).
文摘Nonfullerene acceptors(NFAs),which usually possess symmetric skeletons,have drawn great attention in recent years due to their pronounced advantages over the fullerene counterparts.Moreover,breaking the symmetry of NFAs could fine tune the molecular dipole,solubility,energy level,intermolecular interaction,molecular packing,crystallinity,etc.,and give rise to improved photovoltaic performance.Currently,there are three main strategies for the design of asymmetric NFAs.This review highlights the recent advances of high-performance asymmetric NFAs and briefly outlooks the materials exploration for the future.
基金EPSRC project ATIP,Grant/Award Number:EP/TO28513/1China Scholarship Council(CSC)via the CSC Imperial Scholarship。
文摘The power conversion efficiencies(PCEs)of single-junction organic solar cells(OSCs)have surpassed 19%,owing to the emerging Y-series nonfullerene acceptors(NFAs).Undoubtedly,the power and flexibility of chemical design has been a strong driver for this rapid efficiency improvement in the OSC field.Over the course of the past 3 years,a variety of modifications have been made to the structure of the Y6 acceptor,and a large number of Y-series NFAs have been reported to further improve performance.Herein,we present our insights into the rationale behind the Y6 acceptor and discuss the design principles toward high-performance Y-series NFAs.It is clear that structural modifications through choice of heteroatom,soluble chains,πspacers,central cores,and end groups alter the material characteristics and properties,contributing to distinctive photovoltaic performance.Subsequently,we analyze various design strategies of Y-series-containing materials,including polymerized small-molecule acceptors(PSMA),non-fused-ring acceptors(NFRA),and all-fused-ring acceptors(AFRA).This review is expected to be of value in providing effective molecular design strategies for high-performance NFAs in future innovations.
基金supported by the National Natural Science Foundation of China(52061135206,22279094)the Fundamental Research Funds for the Central Universities。
文摘The performance of organic solar cells(OSCs)is mainly related to the bulk heterojunction(BHJ)microstructure of specific active layer systems,which is often in a metastable state.A promising strategy to address the abovementioned shortcomings of BHJs is to develop single-component active layer materials.Owing to the single-component small molecule materials with defined chemical structures generally exhibit poor absorption spectra,herein we first introduced narrow bandgap Y-series acceptors into the molecular skeleton of single-component materials,and designed two molecular dyads,SM-Et-1Y and SM-Et-2Y.The optical bandgaps(E_g~(opt)s)of the two dyads are 1.364 and 1.361 eV,respectively,which are much smaller than those of previously reported single-component molecules.Consequently,the SM-Et-2Y-based single-component OSCs(SCOSCs)showed a power conversion efficiency(PCE)of 5.07%,superior to SM-Et-1Y(2.53%),which is one of the highest PCEs reported for SCOSCs to date.Moreover,both SM-Et-1Y-and SM-Et-2Y-based devices exhibited excellent photo-stability,retaining over 90%of their initial performance after 250 h of continuous illumination.Our results provide a deeper understanding of the molecular backbone and a guiding principle for the rational design or selection of non-fullerene single-component materials with suitable donor/acceptor ratios.