The emergence of non-fullerene acceptors(NFA) offers a promising opportunity to develop high-performance donor/acceptor pairs with high power conversion efficiency,as NFAs offer tunable energy levels,broad absorption ...The emergence of non-fullerene acceptors(NFA) offers a promising opportunity to develop high-performance donor/acceptor pairs with high power conversion efficiency,as NFAs offer tunable energy levels,broad absorption and suitable aggregation property.In order to enhance light-harvesting capability of active layers,we choose a wide bandgap polymer PTQ10 as the donor to blend with a narrow bandgap NFAY6 as the acceptor.In comparison with PTQ10:IDIC blend,~130 nm red-shifted absorption spectrum is observed in the PTQ10:Y6 blend,which potentially enhance the short-circuit current density(Jsc) for the PSCs.In addition,the optimal PTQ10:Y6 blend shows higher photoluminescence quenching efficiency and more efficient charge separation,higher charge mobilities,as well as weaker bimolecular recombination over the PTQ10:IDIC blend,which leads to an outstanding power conversion efficiency(PCE) of 16.53%,with a notable Jsc of 26.65 mA cm^-2 and fill factor(FF) of 0.751.展开更多
Organic solar cells(OSCs)have unique advantages of light weight,low-cost solution processing,and capability to be fabricated into flexible and semitransparent devices,which are widely recognized as a promising photovo...Organic solar cells(OSCs)have unique advantages of light weight,low-cost solution processing,and capability to be fabricated into flexible and semitransparent devices,which are widely recognized as a promising photovoltaic technology.Photoactive layers of the OSCs are composed of a blend of a p-type organic semiconductor as a donor(D)and an n-type organic semiconductor as acceptor(A).The morphology of the active layer with D/A nano-scaled aggregation and face-onπconjugated packing,and D/A interpenetrating network is crucial for achieving high photovoltaic performance of the OSCs.Therefore,great efforts have been devoted to control and optimize morphology of the active layers.This perspective focuses on the morphological control by solvent/solid processing additives and the morphology optimization by postdeposition treatment with thermal annealing and/or solvent vapor annealing,which have been extensively adopted and exhibit promising positive effect in optimizing the morphology.Representative examples are given and discussed to understand the foundation of the postdeposition treatments on tuning the morphology.Insights into the role of the postdeposition treatments and additive treatments on the morphology optimization will be beneficial to further improvement in morphology optimization for practical organic photovoltaic application.展开更多
CONSPECTUS:Over the past few years,the innovation of narrow bandgap acceptor combined with wide bandgap donor materials significantly promotes the power conversion efficiencies(PCEs)of organic solar cells(OSCs)to exce...CONSPECTUS:Over the past few years,the innovation of narrow bandgap acceptor combined with wide bandgap donor materials significantly promotes the power conversion efficiencies(PCEs)of organic solar cells(OSCs)to exceed 18%.To build a state-of-the-art OSC,absorption spectra,frontier molecular orbital energy levels,molecular packing and crystallinity,and charge carrier mobilities of the photovoltaic materials should be considered in their molecular design.The donor and acceptor materials are the key components determining the photovoltaic performance of the OSCs.The side chain engineering on the conjugated backbone is a critical strategy to optimize the photovoltaic properties of the donor materials.In this Account,we focus on the topic of heteroatom substitution on the molecular backbone of the donor materials for improving their photovoltaic performance,aiming to provide in-depth understanding of the molecular structure optimization for the design of stateof-the-art photovoltaic materials.展开更多
Controlling the photoactive layer morphology towards nanoscale bi-continuous donor/acceptor interpenetrating networks is a key issue to build high-performance organic solar cells(OSCs).Due to the distinct properties b...Controlling the photoactive layer morphology towards nanoscale bi-continuous donor/acceptor interpenetrating networks is a key issue to build high-performance organic solar cells(OSCs).Due to the distinct properties between donor and acceptor materials,casting an active layer from a single solvent solution usually results in either insufficient or excessive phase separation that reduces the device performance.In comparison to the fullerene acceptors with closed-cage structures,the currently dominant non-fullerene acceptors possess the similar anisotropicπ-πinteractions with p-type organic semiconductor donors,giving rise to the complexity of the morphology regulation.Herein,we employ 4,4′-dimethoxyoctafluorobiphenyl(OFP)with strong crystallinity as a volatile solid additive to optimize the active layer morphology of OSCs.The synergistic effect of 1-chloronaphthalene(CN)and OFP as dual additives shows supreme capability on optimizing the morphology over the conventional additive of CN,which is in favor of improving charge transport and suppressing charge recombination for higher fill factors in various systems.In particular,the PTQ10:m-BTP-C6 Ph-based device processed by the additive showed a remarkable powerconversion efficiency(PCE)of 17.74%,whereas the control device processed by CN additive yielded a relatively lower PCE of16.45%.展开更多
All-polymer solar cells(all-PSCs)have attracted tremendous research interests due to their inherent advantages of excellent mechanical flexibility,film formation,and morphological stability.Recently,the development of...All-polymer solar cells(all-PSCs)have attracted tremendous research interests due to their inherent advantages of excellent mechanical flexibility,film formation,and morphological stability.Recently,the development of polymerized small-molecule acceptors(PSMAs)has boosted the power conversion efficiencies(PCEs)of all-PSCs to over 18%.Polymerization sites on the terminal groups of small molecule acceptors play a decisive role in determining the absorption spectra,frontier molecular orbital energy levels,molecular packing and crystallinity,charge carrier mobilities and device performance of polymer acceptors.In this perspective,we focus on the latest advances of region-specific terminal groups and region-regular PSMAs,aiming to summarize the relationship between molecular structure–physicochemical properties–active layer morphology–device performance.Finally,the future design directions and challenges faced by region-specific terminal groups and regionregular PSMAs are discussed.In this Perspective article,we advocate that the region-regular PSMAs approach can advance better designs for high-performance polymer acceptors with good batch-to-batch reproducibility.展开更多
Four metallated conjugated oligothiophenes, S-1, S-2, S-3 and S-4, with platinum（II） aryleneethynylenes as the electron-rich building block were synthesized to investigate their physicochemical and photovoltaic prop...Four metallated conjugated oligothiophenes, S-1, S-2, S-3 and S-4, with platinum（II） aryleneethynylenes as the electron-rich building block were synthesized to investigate their physicochemical and photovoltaic properties. These small molecules possess fairly low-lying HOMO energy levels which match with the LUMO energy level of the electron acceptor PC70BM （[6,6]-phenyl-C71-butyric acid methyl ester）. Using the simple process of spin-coating solution fabrication technique, S-I：PC70BM （1：4, w/w） based organic solar cells exhibiting a high Voc of 0.913 V, with a PCE value of 0.88% were developed. In contrast, the OSC device based on S-2：PC70BM （3：7, w/w） displayed a higher PCE of 1.59% with a higher Jsc value of 5.89 mA cm^-2. The device based on S-4：PCToBM （1：4, w/w） exhibited a PCE value of 1.56%, with a Voc of 0.917 V.展开更多
基金supported by the National Natural Science Foundation of China(51873140,51603136,91633301)
文摘The emergence of non-fullerene acceptors(NFA) offers a promising opportunity to develop high-performance donor/acceptor pairs with high power conversion efficiency,as NFAs offer tunable energy levels,broad absorption and suitable aggregation property.In order to enhance light-harvesting capability of active layers,we choose a wide bandgap polymer PTQ10 as the donor to blend with a narrow bandgap NFAY6 as the acceptor.In comparison with PTQ10:IDIC blend,~130 nm red-shifted absorption spectrum is observed in the PTQ10:Y6 blend,which potentially enhance the short-circuit current density(Jsc) for the PSCs.In addition,the optimal PTQ10:Y6 blend shows higher photoluminescence quenching efficiency and more efficient charge separation,higher charge mobilities,as well as weaker bimolecular recombination over the PTQ10:IDIC blend,which leads to an outstanding power conversion efficiency(PCE) of 16.53%,with a notable Jsc of 26.65 mA cm^-2 and fill factor(FF) of 0.751.
基金National Natural Science Foundation of China,Grant/Award Numbers:22022509,51873140,51820105003。
文摘Organic solar cells(OSCs)have unique advantages of light weight,low-cost solution processing,and capability to be fabricated into flexible and semitransparent devices,which are widely recognized as a promising photovoltaic technology.Photoactive layers of the OSCs are composed of a blend of a p-type organic semiconductor as a donor(D)and an n-type organic semiconductor as acceptor(A).The morphology of the active layer with D/A nano-scaled aggregation and face-onπconjugated packing,and D/A interpenetrating network is crucial for achieving high photovoltaic performance of the OSCs.Therefore,great efforts have been devoted to control and optimize morphology of the active layers.This perspective focuses on the morphological control by solvent/solid processing additives and the morphology optimization by postdeposition treatment with thermal annealing and/or solvent vapor annealing,which have been extensively adopted and exhibit promising positive effect in optimizing the morphology.Representative examples are given and discussed to understand the foundation of the postdeposition treatments on tuning the morphology.Insights into the role of the postdeposition treatments and additive treatments on the morphology optimization will be beneficial to further improvement in morphology optimization for practical organic photovoltaic application.
基金We thank the National Natural Science Foundation of China(22022509,51873140,and 51820105003)Jiangsu Provincial Natural Science Foundation(BK20190095)Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),and Collaborative Innovation Center of Suzhou Nano Science and Technology for financial support。
文摘CONSPECTUS:Over the past few years,the innovation of narrow bandgap acceptor combined with wide bandgap donor materials significantly promotes the power conversion efficiencies(PCEs)of organic solar cells(OSCs)to exceed 18%.To build a state-of-the-art OSC,absorption spectra,frontier molecular orbital energy levels,molecular packing and crystallinity,and charge carrier mobilities of the photovoltaic materials should be considered in their molecular design.The donor and acceptor materials are the key components determining the photovoltaic performance of the OSCs.The side chain engineering on the conjugated backbone is a critical strategy to optimize the photovoltaic properties of the donor materials.In this Account,we focus on the topic of heteroatom substitution on the molecular backbone of the donor materials for improving their photovoltaic performance,aiming to provide in-depth understanding of the molecular structure optimization for the design of stateof-the-art photovoltaic materials.
基金supported by the National Natural Science Foundation of China(22022509,51873140 and 51820105003)Jiangsu Provincial Natural Science Foundation(BK20190095)+1 种基金Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)Collaborative Innovation Center of Suzhou Nano Science and Technology。
文摘Controlling the photoactive layer morphology towards nanoscale bi-continuous donor/acceptor interpenetrating networks is a key issue to build high-performance organic solar cells(OSCs).Due to the distinct properties between donor and acceptor materials,casting an active layer from a single solvent solution usually results in either insufficient or excessive phase separation that reduces the device performance.In comparison to the fullerene acceptors with closed-cage structures,the currently dominant non-fullerene acceptors possess the similar anisotropicπ-πinteractions with p-type organic semiconductor donors,giving rise to the complexity of the morphology regulation.Herein,we employ 4,4′-dimethoxyoctafluorobiphenyl(OFP)with strong crystallinity as a volatile solid additive to optimize the active layer morphology of OSCs.The synergistic effect of 1-chloronaphthalene(CN)and OFP as dual additives shows supreme capability on optimizing the morphology over the conventional additive of CN,which is in favor of improving charge transport and suppressing charge recombination for higher fill factors in various systems.In particular,the PTQ10:m-BTP-C6 Ph-based device processed by the additive showed a remarkable powerconversion efficiency(PCE)of 17.74%,whereas the control device processed by CN additive yielded a relatively lower PCE of16.45%.
基金supported by the National Natural Science Foundation of China(22022509 and 51873140)Jiangsu Provincial Natural Science Foundation(BK20190095)Natural Science Foundation of the Jiangsu Higher Education Institutions of China(21KJA150006).
文摘All-polymer solar cells(all-PSCs)have attracted tremendous research interests due to their inherent advantages of excellent mechanical flexibility,film formation,and morphological stability.Recently,the development of polymerized small-molecule acceptors(PSMAs)has boosted the power conversion efficiencies(PCEs)of all-PSCs to over 18%.Polymerization sites on the terminal groups of small molecule acceptors play a decisive role in determining the absorption spectra,frontier molecular orbital energy levels,molecular packing and crystallinity,charge carrier mobilities and device performance of polymer acceptors.In this perspective,we focus on the latest advances of region-specific terminal groups and region-regular PSMAs,aiming to summarize the relationship between molecular structure–physicochemical properties–active layer morphology–device performance.Finally,the future design directions and challenges faced by region-specific terminal groups and regionregular PSMAs are discussed.In this Perspective article,we advocate that the region-regular PSMAs approach can advance better designs for high-performance polymer acceptors with good batch-to-batch reproducibility.
基金the National Natural Science Foundation of China(51373145)Science,Technology and Innovation Committee of Shenzhen Municipality(JCYJ20120829154440583)+8 种基金the Hong Kong Research Grants Council(HKBU202410)Hong Kong Baptist University(FRG2/12-13/083)for financial supportpartially supported by a grant from the Research Grants Council of the Hong Kong Special Administrative Region,China(T23-713/11)the 111 Projectthe Beijing Engineering Research Center of Food Environment and the Public Health from Minzu University of China(B08044 and 10301-01404026)for financial supportsupported by the Partner State Key Laboratory of Environmental and Biological Analysis(SKLP-14-15-P011)the Strategic Development Fund of HKBUW.C.H.Choy would like to acknowledge the General Research Fund(HKU711813 and HKU711612E)from the Research Grants Council of Hong Kong Special Administrative Region,Chinathe grant CAS14601 from CAS-Croucher Funding Scheme for Joint Laboratories
文摘Four metallated conjugated oligothiophenes, S-1, S-2, S-3 and S-4, with platinum（II） aryleneethynylenes as the electron-rich building block were synthesized to investigate their physicochemical and photovoltaic properties. These small molecules possess fairly low-lying HOMO energy levels which match with the LUMO energy level of the electron acceptor PC70BM （[6,6]-phenyl-C71-butyric acid methyl ester）. Using the simple process of spin-coating solution fabrication technique, S-I：PC70BM （1：4, w/w） based organic solar cells exhibiting a high Voc of 0.913 V, with a PCE value of 0.88% were developed. In contrast, the OSC device based on S-2：PC70BM （3：7, w/w） displayed a higher PCE of 1.59% with a higher Jsc value of 5.89 mA cm^-2. The device based on S-4：PCToBM （1：4, w/w） exhibited a PCE value of 1.56%, with a Voc of 0.917 V.
