Despite the many advantages for industrial mass production,vacuum-deposited organic solar cells(OSCs)suffer from low efficiency,primarily due to the limited molecular library of small-molecule donor and acceptor mater...Despite the many advantages for industrial mass production,vacuum-deposited organic solar cells(OSCs)suffer from low efficiency,primarily due to the limited molecular library of small-molecule donor and acceptor materials,which remains a significant challenge.Herein,two donor–acceptor-acceptor(D-A-A)-configured small-molecule donors,named TTBTDC and TTBTDC-F were synthesized,using 8H-thieno[2′,3′:4,5]thieno[3,2-b]thieno[2,3-d]pyrrole(TTP)as a new fused-ring donor unit.Benefiting from the strong electron-donating ability of the TTP moiety and the adoption of the D-A-A molecular configuration,these molecules exhibited strong visible and near-infrared absorption as well as deep-lying highest occupied molecular orbital(HOMO)energy levels.Consequently,OSCs based on TTBTDC achieved an unprecedented power conversion efficiency(PCE)of 10.28%(certified value of 10.05%)with a short-circuit current density(J_(sc))up to 17.78 mA cm^(−2),representing the highest PCE and J_(sc)values reported to date for vacuum-deposited OSCs.In contrast,OSCs based on TTBTDC-F exhibited an inferior PCE of 8%with slightly higher open-circuit voltage(V_(oc))but lower J_(sc).By systematically investigating the relationships between molecular structure and properties,we found that the high performance of TTBTDC devices results from extended absorption up to 900 nm,stronger cofacial antiparallelπ-πinteractions,and superior charge transport with suppressed recombination.Besides,both TTBTDC and TTBTDC-F devices exhibited excellent device stabilities,including storage stability,thermal stability,and photo-stability.This work demonstrates the great potential of TTP as a building block for constructing small-molecule donors and sheds light on the molecular design of small-molecule donors for high-efficiency and stable vacuum-deposited OSCs.展开更多
Carbon nanohoop,a class of constrained molecular architecture consisting of linked arene units,has attracted considerable interest from both experimental and theoretical chemists due to its synthetic challenge and aes...Carbon nanohoop,a class of constrained molecular architecture consisting of linked arene units,has attracted considerable interest from both experimental and theoretical chemists due to its synthetic challenge and aesthetic architectures.Another fascinating and synthetically challenging species,the Mobius-type molecule,has been attracting the scientific community with its elegant structure and aromaticity.Thus,combining two things together,synthesizing a carbon nanohoop with Mobius topology remains more challenging to date.Here we report a cyclophenylene featuring Mobius strip characterized by X-ray crystallography.Theoretical calculations reveal that such type of nanohoop is fully conjugated systems with electrons delocalized both inπsextets and the bridging carbon–carbon bonds.This work highlights that the manipulation of phenylene connection in a carbon nanohoop can help obtain more delicate and aesthetic molecular architectures.展开更多
Imbalanced charge-carrier extraction remains an issue aggravating interfacial charge accumulation and recombination.More hopping transport channels could accelerate the extraction of charge.Here,we demonstrated an eff...Imbalanced charge-carrier extraction remains an issue aggravating interfacial charge accumulation and recombination.More hopping transport channels could accelerate the extraction of charge.Here,we demonstrated an effective“bridging interface”strategy between the perovskite/2,2′,7,7′-tetrakis(N,N-di-pmethoxyphenylamine)-9,9′-spirobifluorene(spiro-OMeTAD)that modulates interfacial charge transfer and improves hole mobility using radical-containing donor-acceptor nanographenes(D-A NGs)possessing electron-deficient perchlorinated NGs and electron-rich aniline derivatives.The fully delocalized backbone of nanographene formed a conjugated bridge for intermolecular charge transfer and generated stable radical cations,verified by electron spin resonance.Lamellar andπ-πstacking orientation of D-A NGs also provided advantageous hopping transport channels.Besides favorable charge transfer within D-A NGs,systematic explorations indicated a strong interface coupling and noticeable charge transfer across the D-A NGs and perovskite interface,where electrons would flow from D-A NGs to perovskite,and holes would flow from perovskite to D-A NGs.Moreover,the hole mobility of spiro-OMeTAD was also enhanced because the D-A NGs would diffuse into the spiro-OMeTAD layer.As a result,planar n-i-p perovskite solar cellsmodified byD-ANG-OMe/D-ANG-tBudeliveredchampion power conversion efficiencies(PCEs)of 23.25%and 23.51%,respectively.展开更多
基金supported by the National Natural Science Foundation of China(92361303,92061204,and 52203228)the Natural Science Foundation of Guangdong Province of China(2023A1515011916)+1 种基金the China Postdoctoral Science Foundation(2022M712658)Han Young Woo acknowledges the financial support from the National Research Foundation of Korea(2019R1A6A1A11044070,and RS-2024-00334832).
文摘Despite the many advantages for industrial mass production,vacuum-deposited organic solar cells(OSCs)suffer from low efficiency,primarily due to the limited molecular library of small-molecule donor and acceptor materials,which remains a significant challenge.Herein,two donor–acceptor-acceptor(D-A-A)-configured small-molecule donors,named TTBTDC and TTBTDC-F were synthesized,using 8H-thieno[2′,3′:4,5]thieno[3,2-b]thieno[2,3-d]pyrrole(TTP)as a new fused-ring donor unit.Benefiting from the strong electron-donating ability of the TTP moiety and the adoption of the D-A-A molecular configuration,these molecules exhibited strong visible and near-infrared absorption as well as deep-lying highest occupied molecular orbital(HOMO)energy levels.Consequently,OSCs based on TTBTDC achieved an unprecedented power conversion efficiency(PCE)of 10.28%(certified value of 10.05%)with a short-circuit current density(J_(sc))up to 17.78 mA cm^(−2),representing the highest PCE and J_(sc)values reported to date for vacuum-deposited OSCs.In contrast,OSCs based on TTBTDC-F exhibited an inferior PCE of 8%with slightly higher open-circuit voltage(V_(oc))but lower J_(sc).By systematically investigating the relationships between molecular structure and properties,we found that the high performance of TTBTDC devices results from extended absorption up to 900 nm,stronger cofacial antiparallelπ-πinteractions,and superior charge transport with suppressed recombination.Besides,both TTBTDC and TTBTDC-F devices exhibited excellent device stabilities,including storage stability,thermal stability,and photo-stability.This work demonstrates the great potential of TTP as a building block for constructing small-molecule donors and sheds light on the molecular design of small-molecule donors for high-efficiency and stable vacuum-deposited OSCs.
基金This work was supported by the National Natural Science Foundation of China(21873079,21771155,92061103,21721001,21573179)the Ministry of Science and Technology of China(2017YFA0204902)+1 种基金the Fundamental Research Funds for the Central Universities(20720180035)the Top-Notch Young Talents Program of China.
文摘Carbon nanohoop,a class of constrained molecular architecture consisting of linked arene units,has attracted considerable interest from both experimental and theoretical chemists due to its synthetic challenge and aesthetic architectures.Another fascinating and synthetically challenging species,the Mobius-type molecule,has been attracting the scientific community with its elegant structure and aromaticity.Thus,combining two things together,synthesizing a carbon nanohoop with Mobius topology remains more challenging to date.Here we report a cyclophenylene featuring Mobius strip characterized by X-ray crystallography.Theoretical calculations reveal that such type of nanohoop is fully conjugated systems with electrons delocalized both inπsextets and the bridging carbon–carbon bonds.This work highlights that the manipulation of phenylene connection in a carbon nanohoop can help obtain more delicate and aesthetic molecular architectures.
基金the financial support from the National Natural Science Foundation of China(grant nos.21975260 and 22175180)the National Natural Science Foundation of China-National Research Council of Italy(NSFC-CNR)Exchange Program of NSFC(grant no.22011530391)The GIWAXS measurements were performed at SPring-8 with the approval of the Japan Synchrotron Radiation Research Institute(grant nos.2022A1654,2022A1777,and 2022A1822).
文摘Imbalanced charge-carrier extraction remains an issue aggravating interfacial charge accumulation and recombination.More hopping transport channels could accelerate the extraction of charge.Here,we demonstrated an effective“bridging interface”strategy between the perovskite/2,2′,7,7′-tetrakis(N,N-di-pmethoxyphenylamine)-9,9′-spirobifluorene(spiro-OMeTAD)that modulates interfacial charge transfer and improves hole mobility using radical-containing donor-acceptor nanographenes(D-A NGs)possessing electron-deficient perchlorinated NGs and electron-rich aniline derivatives.The fully delocalized backbone of nanographene formed a conjugated bridge for intermolecular charge transfer and generated stable radical cations,verified by electron spin resonance.Lamellar andπ-πstacking orientation of D-A NGs also provided advantageous hopping transport channels.Besides favorable charge transfer within D-A NGs,systematic explorations indicated a strong interface coupling and noticeable charge transfer across the D-A NGs and perovskite interface,where electrons would flow from D-A NGs to perovskite,and holes would flow from perovskite to D-A NGs.Moreover,the hole mobility of spiro-OMeTAD was also enhanced because the D-A NGs would diffuse into the spiro-OMeTAD layer.As a result,planar n-i-p perovskite solar cellsmodified byD-ANG-OMe/D-ANG-tBudeliveredchampion power conversion efficiencies(PCEs)of 23.25%and 23.51%,respectively.
