High-performance as-cast organic solar cells(OSCs)are rarely reported due to the challenges in achieving high-quality active layer morphology via a single-step process.Herein,four small molecule acceptors(SMAs)substit...High-performance as-cast organic solar cells(OSCs)are rarely reported due to the challenges in achieving high-quality active layer morphology via a single-step process.Herein,four small molecule acceptors(SMAs)substituted with cyclic alkyl chains of varying carbon numbers were synthesized and utilized to fabricate highly efficient as-cast OSCs.The side-chain cyclization strategy significantly enhances molecular rigidity and strengthens intermolecular packing,particularly in Se-Cb,which exhibits an excellent three-dimensional(3D)stacking framework with aπ-πstacking distance as short as 3.34A.As the size of cyclic alkyl chain increases,the packing mode of SMA single crystals shift from 3D to 2D,accompanied by a greaterπ-πstacking distance due to increased steric hindrance.As-cast binary devices based on D18/Se-Cb achieved a record power conversion efficiency(PCE)of 19.1%with a fill factor(FF)exceeding 80%,and a certified value of 18.45%.Se-Cb forms a more uniform vertical phase separation morphology than the control SMA within the D18 matrix,enhancing carrier transport and significantly suppressing sub-nanosecond bimolecular recombination.This study systematically investigates the effects of cyclic alkyl chain substitution on the properties and photovoltaic performance of SMAs,identifying cyclobutyl as a promising candidate for efficient as-cast OSCs with high FF.展开更多
1 Results In recent years,interests in organic semiconductor have increased due to the applications in optoelectronic devices such as organic light-emitting diodes (OLEDs)[1],field-effect transistors (FETs)[2],and pho...1 Results In recent years,interests in organic semiconductor have increased due to the applications in optoelectronic devices such as organic light-emitting diodes (OLEDs)[1],field-effect transistors (FETs)[2],and photovoltaic devices[3]. These organic electronics have several advantages over conventional inorganic electronics including facile processability,chemical tunability,compatibility with plastic substrates,and low cost to fabricate. Selenophene-based molecules show good π-conjugating electron o...展开更多
基金supported by the National Natural Science Foundation of China(U23A20371,U21A2078)the Scientific Research Funds of Huaqiao University(605-50Y23024)the PolyU Distinguished Postdoctoral Fellowship(1-YW4C)。
文摘High-performance as-cast organic solar cells(OSCs)are rarely reported due to the challenges in achieving high-quality active layer morphology via a single-step process.Herein,four small molecule acceptors(SMAs)substituted with cyclic alkyl chains of varying carbon numbers were synthesized and utilized to fabricate highly efficient as-cast OSCs.The side-chain cyclization strategy significantly enhances molecular rigidity and strengthens intermolecular packing,particularly in Se-Cb,which exhibits an excellent three-dimensional(3D)stacking framework with aπ-πstacking distance as short as 3.34A.As the size of cyclic alkyl chain increases,the packing mode of SMA single crystals shift from 3D to 2D,accompanied by a greaterπ-πstacking distance due to increased steric hindrance.As-cast binary devices based on D18/Se-Cb achieved a record power conversion efficiency(PCE)of 19.1%with a fill factor(FF)exceeding 80%,and a certified value of 18.45%.Se-Cb forms a more uniform vertical phase separation morphology than the control SMA within the D18 matrix,enhancing carrier transport and significantly suppressing sub-nanosecond bimolecular recombination.This study systematically investigates the effects of cyclic alkyl chain substitution on the properties and photovoltaic performance of SMAs,identifying cyclobutyl as a promising candidate for efficient as-cast OSCs with high FF.
文摘1 Results In recent years,interests in organic semiconductor have increased due to the applications in optoelectronic devices such as organic light-emitting diodes (OLEDs)[1],field-effect transistors (FETs)[2],and photovoltaic devices[3]. These organic electronics have several advantages over conventional inorganic electronics including facile processability,chemical tunability,compatibility with plastic substrates,and low cost to fabricate. Selenophene-based molecules show good π-conjugating electron o...
