Organic solar cells(OSCs)have received great attention for the prominent advantage of low-cost,light-weight and potential for fabricating flexible and semi-transparent device via roll-to-roll printing toward making be...Organic solar cells(OSCs)have received great attention for the prominent advantage of low-cost,light-weight and potential for fabricating flexible and semi-transparent device via roll-to-roll printing toward making better use of inexhaustible renewable clean energy during the past years[1-4].展开更多
Among various perylenediimide(PDI)-based small molecular non-fullerene acceptors(NFAs),PDI dimer can effectively avoid the excessive aggregation of single PDI and improve the photovoltaic performance.However,the twist...Among various perylenediimide(PDI)-based small molecular non-fullerene acceptors(NFAs),PDI dimer can effectively avoid the excessive aggregation of single PDI and improve the photovoltaic performance.However,the twist of perylene core in PDI dimer will destroy the effective conjugation.Thus,ring annulation of PDI dimer is a feasible method to balance the film quality and electron transport,but the systematic study has attracted few attentions.Herein,we choose a simple vinylene linked PDI dimer,V-PDI2,and then conduct further studies on the structure-property-performance relationship of four kinds of derived fused-PDI dimers,namely V-TDI2,V-FDI2,V-PDIS2 and V-PDISe2 respectively.The former two are incorporated thianaphthene and benzofuran at the inside bay positions,and the latter two are fused thiophene and selenophene at the outside bay positions,respectively.Theoretical calculations reveal the inside-and outside-fused structures largely affect the skeleton configuration,the former two tend to be planar structure and the latter two maintain the distorted backbone.The photovoltaic characterizations show that the inside-fused PDI dimers offer high open circuit voltage(VOC),while the outside-fused PDI dimers afford large short-circuit current density(JSC).This variation tendency results from the reasonably tunable energy levels,light absorption,molecular crystallinity and film morphology.As a result,PBDB-T:V-PDISe2 device exhibits the highest power conversion efficiency(PCE)of 6.51%,and PBDB-T:VFDI2 device realizes the highest VOC of 1.00 V.This contribution indicates that annulation of PDI dimers in outside or inside bay regions is a feasible method to modulate the properties of PDI-based non-fullerene acceptors.展开更多
基金The authors thank the support from the National Key Research and Development Program of China(2017YFA0206600)the Key Research Program of Frontier Sciences,Chinese Academy of Sciences(Grant No.QYZDB-SSW-SLH033)+1 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB36000000)the National Natural Science Foundation of China(NSFC,Nos.21875052,51873044,52073067).
文摘Organic solar cells(OSCs)have received great attention for the prominent advantage of low-cost,light-weight and potential for fabricating flexible and semi-transparent device via roll-to-roll printing toward making better use of inexhaustible renewable clean energy during the past years[1-4].
基金supported by the National Key Research and Development Program of China (2017YFA0206600)the Key Research Program of Frontier Sciences, Chinese Academy of Sciences (Grant No. QYZDB-SSW-SLH033)the National Natural Science Foundation of China (NSFC, Nos. 51473040, 51673048, 21875052, 51673092)
文摘Among various perylenediimide(PDI)-based small molecular non-fullerene acceptors(NFAs),PDI dimer can effectively avoid the excessive aggregation of single PDI and improve the photovoltaic performance.However,the twist of perylene core in PDI dimer will destroy the effective conjugation.Thus,ring annulation of PDI dimer is a feasible method to balance the film quality and electron transport,but the systematic study has attracted few attentions.Herein,we choose a simple vinylene linked PDI dimer,V-PDI2,and then conduct further studies on the structure-property-performance relationship of four kinds of derived fused-PDI dimers,namely V-TDI2,V-FDI2,V-PDIS2 and V-PDISe2 respectively.The former two are incorporated thianaphthene and benzofuran at the inside bay positions,and the latter two are fused thiophene and selenophene at the outside bay positions,respectively.Theoretical calculations reveal the inside-and outside-fused structures largely affect the skeleton configuration,the former two tend to be planar structure and the latter two maintain the distorted backbone.The photovoltaic characterizations show that the inside-fused PDI dimers offer high open circuit voltage(VOC),while the outside-fused PDI dimers afford large short-circuit current density(JSC).This variation tendency results from the reasonably tunable energy levels,light absorption,molecular crystallinity and film morphology.As a result,PBDB-T:V-PDISe2 device exhibits the highest power conversion efficiency(PCE)of 6.51%,and PBDB-T:VFDI2 device realizes the highest VOC of 1.00 V.This contribution indicates that annulation of PDI dimers in outside or inside bay regions is a feasible method to modulate the properties of PDI-based non-fullerene acceptors.
