Abundant interfacial defects remain a significant challenge that hampers both the efficiency and stability of perovskite solar cells(PSCs).Herein,an alcohol-dispersed conducting polymer complex,denoted as PEDOT:F(Poly...Abundant interfacial defects remain a significant challenge that hampers both the efficiency and stability of perovskite solar cells(PSCs).Herein,an alcohol-dispersed conducting polymer complex,denoted as PEDOT:F(Poly(3,4-ethylene dioxythiophene):Perfluorinated sulfonic acid ionomers),is introduced into the interface between perovskite and hole transporting layer in regular-structured PSCs.PEDOT:F serves as a multi-functional interface layer(filling grain boundaries and covering perovskite's grain-surface)to achieve a robust interaction with organic groups within perovskites,which could induce a structural transformation of PEDOT to increase its conductivity for the efficient hole-transport.Furthermore,the strong interaction between PEDOT and perovskites could promote an effective coupling of undercoordinated Pb~(2+)ions with the lone electron pairs near O&S atoms in PEDOT molecules,thereby enhancing defect passivation.Additionally,PEDOT:F with inherent hydrophobic properties prevents effectively moisture invasion into perovskites for the improved long-term stability of the PSCs.Consequently,the PEDOT:F-based PSCs achieved a champion efficiency of 24.81%,and maintained ca.92%of their initial efficiency after 7680 h of storage in a dry air environment,accompanied by the enhanced photothermal stability.展开更多
Enhancing the lifetime of perovskite solar cells(PSCs)is one of the essential challenges for their industrialization.Although the external encapsulation protects the perovskite device from the erosion of moisture and ...Enhancing the lifetime of perovskite solar cells(PSCs)is one of the essential challenges for their industrialization.Although the external encapsulation protects the perovskite device from the erosion of moisture and oxygen under various harsh conditions.However,the perovskite devices still undergo static and dynamic thermal stress during thermal and thermal cycling aging,respectively,resulting in irreversible damage to the morphology,component,and phase of stacked materials.Herein,the viscoelastic polymer polyvinyl butyral(PVB)material is designed onto the surface of perovskite films to form flexible interface encapsulation.After PVB interface encapsulation,the surface modulus of perovskite films decreases by nearly 50%,and the interface stress range under the dynamic temperature field(−40 to 85°C)drops from−42.5 to 64.8 MPa to−14.8 to 5.0 MPa.Besides,PVB forms chemical interactions with FA+cations and Pb^(2+),and the macroscopic residual stress is regulated and defects are reduced of the PVB encapsulated perovskite film.As a result,the optimized device's efficiency increases from 22.21%to 23.11%.Additionally,after 1500 h of thermal treatment(85°C),1000 h of damp heat test(85°C&85%RH),and 250 cycles of thermal cycling test(−40 to 85°C),the devices maintain 92.6%,85.8%,and 96.1%of their initial efficiencies,respectively.展开更多
Lead halide perovskite solar cells(PSCs) have become a promising next-generation photovoltaic technology due to their skyrocketed power conversion efficiency. However, the device stability issues may restrict their co...Lead halide perovskite solar cells(PSCs) have become a promising next-generation photovoltaic technology due to their skyrocketed power conversion efficiency. However, the device stability issues may restrict their commercial applications, which are dominated by various chemical reactions of perovskite layers. Hence, a comprehensive illustration on the stability of perovskite films in PSCs is urgently needed. In this review article, chemical reactions of perovskite films under different environmental conditions(e.g., moisture,oxygen, light) and with charge transfer materials and metal electrodes are systematically elucidated. Effective strategies for suppressing the degradation reactions of perovskites, such as buffer layer introduction and additives engineering,are specified. Finally, conclusions and outlooks for this field are proposed. The comprehensive review will provide a guideline on the material engineering and device design for PSCs.展开更多
It is of vital importance to improve the long-term and photostability of organic photovoltaics,including organic solar cells(OSCs)and organic photodetectors(OPDs),for their ultimate industrialization.Herein,two series...It is of vital importance to improve the long-term and photostability of organic photovoltaics,including organic solar cells(OSCs)and organic photodetectors(OPDs),for their ultimate industrialization.Herein,two series of terpolymers featuring with an antioxidant butylated hydroxytoluene(BHT)-terminated side chain,PTzBI-EHp-BTBHTx and N2200-BTBHTx(x=0.05,0.1,0.2),are designed and synthesized.It was found that incorporating appropriate ratio of benzothiadiazole(BT)with BHT side chains on the conjugated backbone would induce negligible effect on the molecular weight,absorption spectra and energy levels of polymers,however,which would obviously enhance the photostability of these polymers.Consequently,all-polymer solar cells(all-PSCs)and photodetectors were fabricated,and the all-PSC based on PTzBI-EHp-BTBHT0.05:N2200 realized an optimal power conversion efficiency(PCE)approaching~10%,outperforming the device based on pristine PTzBI-EHp:N2200.Impressively,the all-PSCs based on BHT-featuring terpolymers displayed alleviated PCEs degradation under continuous irradiation for 300 h due to the improved morphological and photostability of active layers.The OPDs based on BHT-featuring terpolymers achieved a lower dark current at−0.1 bias,which could be stabilized even after irradiation over 400 h.This study provides a feasible approach to develop terpolymers with antioxidant efficacy for improving the lifetime of OSCs and OPDs.展开更多
ZnO nanoparticles are widely used for the electron transport layers(ETLs)of quantum dots light emitting devices(QLEDs).In this work we show that incorporating fluorine(F)into the ZnO ETL results in significant enhance...ZnO nanoparticles are widely used for the electron transport layers(ETLs)of quantum dots light emitting devices(QLEDs).In this work we show that incorporating fluorine(F)into the ZnO ETL results in significant enhancement in device electroluminescence stability,leading to LT50 at 100 cd m^(−2) of 2,370,000 h in red QLED,47X longer than the control devices.X-ray photo-electron spectroscopy,time-of-flight secondary ion mass spectroscopy,photoluminescence and electrical measurements show that the F passivates oxygen vacancies and reduces electron traps in ZnO.Transient photoluminescence versus bias measurements and capacitance-voltage-luminance measurements reveal that the CF4 plasma-treated ETLs lead to increased electron concentration in the QD and the QD/hole transport layer interface,subsequently decreasing hole accumulation,and hence the higher stability.The findings provide new insights into the critical roles that optimizing charge distribution across the layers play in influencing stability and present a novel and simple approach for extending QLED lifetimes.展开更多
Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were d...Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were developed by Mitsubishi-Hitachi Metals Machinery,Inc.(hereinafter referred to as M-H),including the evolution of the pair cross mill,mill stabilizing device,on-line roll profiler,shape meter for hot-rolling,endless hot-rolling, recent application of UCM,and M-H split housing type 20-high mill.展开更多
Organic solar cells(OSCs)have attracted attention due to their lightweight nature,flexibility,and facile preparation using solution-based methods.Their efficiency has been further elevated by the rapid advancement of ...Organic solar cells(OSCs)have attracted attention due to their lightweight nature,flexibility,and facile preparation using solution-based methods.Their efficiency has been further elevated by the rapid advancement of nonfullerene materials,achieving individual cell efficiencies that surpass 19%.Hence,the stability of nonfullerene solar cell production must be scrutinized.The stability of the cathode interface layer significantly impacts the overall stability of OSC devices.PFN-Br,a commonly employed cathode interface material,is susceptible to degradation due to its sensitivity to environmental humidity,consequently compromising the device stability.In this study,we introduce fluorescent dye molecules,rhodamine 101,as cathode interface layers in OSCs to establish device stability and assess their universality.A comparative investigation of rhodamine 101 and PFN-Br devices demonstrates the former’s distinct advantages in terms of thermal stability,photostability,and storage stability even without encapsulation,particularly in an inert environment.By employing the Kelvin probe,we compare the work function of different cathode interface films and reveal that the work function of the rhodamine 101 interface material remains relatively unaffected by environmental factors.As a consequence,the device performance stability is significantly enhanced.The application of such fluorescent dye molecules extends the scope of cathode interface layers,amplifies device stability,and propels industrialization.展开更多
Additives play a crucial role in enhancing the photovoltaic performance of polymer solar cells(PSCs).However,the typical additives used to optimize blend morphology of PSCs are still high boiling-point solvents,while ...Additives play a crucial role in enhancing the photovoltaic performance of polymer solar cells(PSCs).However,the typical additives used to optimize blend morphology of PSCs are still high boiling-point solvents,while their trace residues may reduce device stability.Herein,an effective strategy of“solidification of solvent additive(SSA)”has been developed to convert additive from liquid to solid,by introducing a covalent bond into low-cost solvent diphenyl sulfide(DPS)to synthesize solid dibenzothiophene(DBT)in one-step,which achieves optimized morphology thus promoting efficiency and device stability.Owing to the fine planarity and volatilization of DBT,the DBT-processed films achieve ordered molecular crystallinity and suitable phase separation compared to the additive-free or DPS-treated ones.Importantly,the DBT-processed device also possesses improved light absorption,enhanced charge transport,and thus a champion efficiency of 17.9%is achieved in the PM6:Y6-based PSCs with an excellent additive component tolerance,reproducibility,and stability.Additionally,the DBT-processed PM6:L8-BO-based PSCs are further fabricated to study the universality of SSA strategy,offering an impressive efficiency approaching19%as one of the highest values in binary PSCs.In conclusion,this article developed a promising strategy named SSA to boost efficiency and improve stability of PSCs.展开更多
A self-powered ultraviolet photodetector(UV PD)with van der Waals(vdW)Schottky junction based on TiO_(2) nanorod arrays/Au-modulated V2 CTx MXene is reported.The Schottky junction enables the device to operate in self...A self-powered ultraviolet photodetector(UV PD)with van der Waals(vdW)Schottky junction based on TiO_(2) nanorod arrays/Au-modulated V2 CTx MXene is reported.The Schottky junction enables the device to operate in self-powered mode.The dangling bond-free surface of V2 CTx MXene reduces the charge recombination at the junction interface.Meanwhile,V2 CTx MXene,with the work function(WF)increasing to 5.35 eV,forms a hole transport layer by contacting with Au electrode,which facilitates the carrier extraction.The electron lifetime in the device has prolonged to 8.95μs.As a result,the responsivity and detectivity of the PD have achieved 28 mA/W and 1.2×10^(11) cm Hz1/2/W(340 nm,65 mW/cm2,0 V),respectively.In addition,the presence of the Au electrode prevents the vanadium from coming into contact with oxygen and oxidizing,preserving the properties of the V2 CTx films.After 180 days of exposure to the atmosphere,the device performance remained at a particularly high level,indicating enhanced durability.This work points out an effective approach to modulate the properties of V2 CTx to obtain the high performance and stability of the UV PD.展开更多
Perovskite solar cells have experienced an unprecedented rapid development in the power conversion efficiency（PCE）during the past 7 years,and the record PCE has been already comparable to the traditional polycrystal...Perovskite solar cells have experienced an unprecedented rapid development in the power conversion efficiency（PCE）during the past 7 years,and the record PCE has been already comparable to the traditional polycrystalline silicon solar cells.Presently,it is more urgent to address the challenge on device stability for the future commercial application.Recently,the inorganic cesium lead halide perovskite has been intensively studied as one of the alternative candidates to improve device stability through controlling the phase transition.The cesium（Cs）-doped perovskites show more superior stability comparing with organic methylammonium（MA）lead halide perovskite or formamidinium（FA）lead halide perovskite.Here,recent progress of the inorganic cesium application in organic-inorganic perovskite solar cells（PSCs）is highlighted from the viewpoints of the device efficiency and the device stability.展开更多
Highly efficient and stable polymer solar cells （PSCs） have been fabricated by adopting solution-derived hybrid poly（ethylene glycol）-titanium oxide （PEG-TiOx） nanocomposite films as a novel and universal cathod...Highly efficient and stable polymer solar cells （PSCs） have been fabricated by adopting solution-derived hybrid poly（ethylene glycol）-titanium oxide （PEG-TiOx） nanocomposite films as a novel and universal cathode buffer layer （CBL）, which can greatly improve device performance by reducing interface energy barriers and enhancing charge extraction/collection. The performance of inverted PSCs with varied bulk-heterojunctions （BHJs） based on this hybrid nanocomposite CBL was found to be much better than those of control devices with a pure TiOx CBL or without a CBL. An excellent power conversion efficiency up to 9.05% under AM 1.5G irradiation （100 mW-cm^-2） was demonstrated, which represents a record high value for inverted PSCs with TiOx-based interface materials.展开更多
There has been an increasing demand for high-performance and cost-effective organic electron-transport materials for organic light-emitting diodes （OLEDs）. In this contribution, we present a simple compound 3-（3-（...There has been an increasing demand for high-performance and cost-effective organic electron-transport materials for organic light-emitting diodes （OLEDs）. In this contribution, we present a simple compound 3-（3-（4,6-diphenyl-l,3,5-triazin-2-yl）phenyl）-1,10-phenanthroline through the facile Pd-catalyzed coupling of a triphenyltriazine boronic ester with 3-hromo-1,10-phenanthroline. It shows a high Tg of 112℃. The ultraviolet photoelectron spectroscopy measurements reveal a deep HOMO level of -6.5 eV. The LUMO level is derived as -3.0 eV, based on the optical bandgap. The low-temperature solid-state phosphorescent spectrum gives a triplet energy of -2.36eV. n-Doping with 8-hydroxyquinolatolithium （Liq, 1：1） leads to considerably improved electron mobility of 5.2 × 10 -6 -5.8 × 10 -5 cm2 v-1 S-1 at E=（2-5） × 10 5Vcm -1, in contrast with the triarylphosphine oxide- phenantroline molecular conjugate we reported previously. It has been shown that through optimizing the device structure and hence suppressing polaron-exciton annihilation, introducing this single Liq-doped electron-transport layer could offer high-efficiency and stable phosphorescent OLEDs.展开更多
An alcohol-soluble,environmentally friendly,and low-cost surfactant-encapsulated polyoxometalate complex[(C8H17)4N]4[SiW_(12)O40](TOASiW_(12))as a cathode interlayer(CIL)has exhibited excellent universality for variou...An alcohol-soluble,environmentally friendly,and low-cost surfactant-encapsulated polyoxometalate complex[(C8H17)4N]4[SiW_(12)O40](TOASiW_(12))as a cathode interlayer(CIL)has exhibited excellent universality for various active layers and cathodes in nonfullerene polymer solar cells(NF-PSCs).In particular,incorporating TOASiW_(12) as the CIL enhanced power conversion efficiencies(PCEs)of the PM6:Y6-based NF-PSCs with Al or Ag cathode to 16.14%and 15.89%,respectively,and the PCEs of PM6:BTP-BO4Cl-based NF-PSCs with Al or Ag cathode to 17.04%and 17.00%,respectively.More importantly,the performances of the devices with TOASiW_(12) were insensitive to the TOASiW_(12) thickness from 3 to 33 nm.Furthermore,the NF-PSCs with TOASiW_(12) exhibited better device stability.Combined characterization of the photocurrent density versus effective voltage,capacitance versus voltage and electron mobility demonstrated that TOASiW_(12) as the CIL effectively promoted exciton dissociation,charge-carrier extraction,built-in potential,charge-carrier density,and electron mobility in the NF-PSCs.These findings suggest that TOASiW_(12) is a promising,competitive CIL for NF-PSCs fabricated by roll-to-roll processing.展开更多
Although the photovoltaic efficiency of organic solar cells(OSCs)has exceeded 17%,poor lifetime excludes OSCs from practical use.In particular,UV rays in sunlight may cause the decomposition of organic photovoltaic ma...Although the photovoltaic efficiency of organic solar cells(OSCs)has exceeded 17%,poor lifetime excludes OSCs from practical use.In particular,UV rays in sunlight may cause the decomposition of organic photovoltaic materials,which has been proved to be the main reason for the efficiency decay.At present,there is still no effective approach to substantially improve the device stability.Herein,we fabricate a highly efficient OSC with exceptional stability under sunlight illumination by incorporating a UV-resistant cathode interlayer(CIL),namely(sulfobetaine-N,Ndimethylamino)propyl naphthalene diimide(NDI-B).NDI-B was designed and synthesized based on the naphthalene diimide(NDI)unit,thereby exhibiting excellent capability of electron collection.Moreover,NDI-B shows strong absorption in the UV region and has good UV resistance.Devices using NDI-B as a CIL exhibited a photovoltaic efficiency of 17.2%,representing the state-of-the-art photovoltaic performance of OSCs.Notably,the NDI-B-modified OSC exhibited a T80 of over 1800 h under full-sun AM 1.5 G illumination(100 mW cm^(−2)),which represents the best stability for OSCs.We demonstrate that the unique ability of the NDI-B interlayer to convert UV light to an additional photocurrent can effectively protect photovoltaic materials from UV-induced decomposition,which is the key to obtain high OSC stability under operational conditions.展开更多
Clusters of water molecules have low ionization energies because of stabilization of charge from the dipole moment of surrounding molecules,and thus can form potential traps resulting in the undesirable photovoltaic p...Clusters of water molecules have low ionization energies because of stabilization of charge from the dipole moment of surrounding molecules,and thus can form potential traps resulting in the undesirable photovoltaic performance in organic solar cells(OSCs).Herein,we demonstrated a solvent-water evaporation(SWE)strategy,which can effectively remove the water-induced traps that are omnipresent in photoactive layers,leading to a significant improvement in device performance.A higher power conversion efficiency of 17.10%and a better device photostability are achieved by using this SWE method,as compared with the untreated binary PM6:Y6 system(15.83%).We highlight the water-related traps as a limiting factor for carrier transport and extraction properties,and further reveal the good universality of the SWE strategy applied into OSCs.In addition,organic light-emitting diodes and organic field-effect transistors are investigated to demonstrate the applicability of this SWE approach.This strategy presents a major step forward for advancing the field of organic electronics.展开更多
Interfacial regulation,serving multiple roles,is critical for the fabrication of stable and efficient organic photovoltaics(OPVs).Herein,a multifunctional cathode interlayer PDINO(15 nm)is prepared by regulating film ...Interfacial regulation,serving multiple roles,is critical for the fabrication of stable and efficient organic photovoltaics(OPVs).Herein,a multifunctional cathode interlayer PDINO(15 nm)is prepared by regulating film thickness,which is inserted between active components and stable silver electrode to align work function,and maintain good interfacial contact and device stability.The thick film can help to reduce interfacial surface defects,keep stable surface morphology,and block the silver diffusion into the active layer.Consequently,the optimal PM6:Y6 device records an impressive power conversion efficiency(PCE)of 17.48%with minimized non-radiative recombination loss of 0.239 V.More importantly,the unencapsulated device maintains 91%of the original PCE after aging for over 60 days at 25℃ and 10%relative humidity in dark conditions.Meanwhile,the PM6:eC9 device achieves a remarkable PCE of 18.22%with the enhancement of open-circuit voltage(V_(oc)).Furthermore,the 1 cm^(2) device-based PDINO(15 nm)/Ag shows a high PCE of 15.2%while only 12.6%for PDINO(9 nm)/Al,indicating the good compatibility of PDINO(15 nm)interlayer with the R2R coating processes used in large-area OPVs fabrication.This work highlights the promise of interfacial regulation to simultaneously stabilize and enhance the efficiency of organic photovoltaics.展开更多
基金supported by the Science Foundation(K201827)the Open Foundation of Hubei Key Laboratory of Optical Information and Pattern Recognition(202103,202206)the Graduate Education Innovation Fund of Wuhan Institute of Technology(CX2023279,CX2023277,CX2023272)。
文摘Abundant interfacial defects remain a significant challenge that hampers both the efficiency and stability of perovskite solar cells(PSCs).Herein,an alcohol-dispersed conducting polymer complex,denoted as PEDOT:F(Poly(3,4-ethylene dioxythiophene):Perfluorinated sulfonic acid ionomers),is introduced into the interface between perovskite and hole transporting layer in regular-structured PSCs.PEDOT:F serves as a multi-functional interface layer(filling grain boundaries and covering perovskite's grain-surface)to achieve a robust interaction with organic groups within perovskites,which could induce a structural transformation of PEDOT to increase its conductivity for the efficient hole-transport.Furthermore,the strong interaction between PEDOT and perovskites could promote an effective coupling of undercoordinated Pb~(2+)ions with the lone electron pairs near O&S atoms in PEDOT molecules,thereby enhancing defect passivation.Additionally,PEDOT:F with inherent hydrophobic properties prevents effectively moisture invasion into perovskites for the improved long-term stability of the PSCs.Consequently,the PEDOT:F-based PSCs achieved a champion efficiency of 24.81%,and maintained ca.92%of their initial efficiency after 7680 h of storage in a dry air environment,accompanied by the enhanced photothermal stability.
基金the National Natural Science Foundation of China(U21A20172,21975028)the China Postdoctoral Science Foundation under Grant Number 2023 M740167.
文摘Enhancing the lifetime of perovskite solar cells(PSCs)is one of the essential challenges for their industrialization.Although the external encapsulation protects the perovskite device from the erosion of moisture and oxygen under various harsh conditions.However,the perovskite devices still undergo static and dynamic thermal stress during thermal and thermal cycling aging,respectively,resulting in irreversible damage to the morphology,component,and phase of stacked materials.Herein,the viscoelastic polymer polyvinyl butyral(PVB)material is designed onto the surface of perovskite films to form flexible interface encapsulation.After PVB interface encapsulation,the surface modulus of perovskite films decreases by nearly 50%,and the interface stress range under the dynamic temperature field(−40 to 85°C)drops from−42.5 to 64.8 MPa to−14.8 to 5.0 MPa.Besides,PVB forms chemical interactions with FA+cations and Pb^(2+),and the macroscopic residual stress is regulated and defects are reduced of the PVB encapsulated perovskite film.As a result,the optimized device's efficiency increases from 22.21%to 23.11%.Additionally,after 1500 h of thermal treatment(85°C),1000 h of damp heat test(85°C&85%RH),and 250 cycles of thermal cycling test(−40 to 85°C),the devices maintain 92.6%,85.8%,and 96.1%of their initial efficiencies,respectively.
基金financially supported by the Research Grants Council (RGC) of Hong Kong, China (Project No. 15306822)Innovation and Technology Commission of Hong Kong, China (Innovation and Technology Fund-Guangdong-Hong Kong Technology Cooperation Funding Scheme (ITF-TCFS), Project No. GHP/042/19SZ)+2 种基金financially supported by the Research Institute of Intelligent Wearable Systems of the Hong Kong Polytechnic University, Hong Kong, China (Project Code: CD46)supported by the funding for Projects of Strategic Importance of the Hong Kong Polytechnic University (Project Code: 1-ZE2X)supported by Shenzhen Science and Technology Innovation Commission, (Project No.: SGDX20210823103401011)。
文摘Lead halide perovskite solar cells(PSCs) have become a promising next-generation photovoltaic technology due to their skyrocketed power conversion efficiency. However, the device stability issues may restrict their commercial applications, which are dominated by various chemical reactions of perovskite layers. Hence, a comprehensive illustration on the stability of perovskite films in PSCs is urgently needed. In this review article, chemical reactions of perovskite films under different environmental conditions(e.g., moisture,oxygen, light) and with charge transfer materials and metal electrodes are systematically elucidated. Effective strategies for suppressing the degradation reactions of perovskites, such as buffer layer introduction and additives engineering,are specified. Finally, conclusions and outlooks for this field are proposed. The comprehensive review will provide a guideline on the material engineering and device design for PSCs.
基金The work was financially supported by National Key Research and Development Program of China(2019YFA0705900,2022YFB4200400)funded by MOSTthe Basic and Applied Basic Research Major Program of Guangdong Province(No.2019B030302007)+2 种基金the National Natural Science Foundation of China(No.U21A6002)Guangdong-Hong Kong-Macao joint laboratory of optoelectronic and magnetic functional materials(No.2019B121205002)C.Z.acknowledges the financial support by Basic and Applied Basic Research Major Program of Guangdong Province(No.202201010270).
文摘It is of vital importance to improve the long-term and photostability of organic photovoltaics,including organic solar cells(OSCs)and organic photodetectors(OPDs),for their ultimate industrialization.Herein,two series of terpolymers featuring with an antioxidant butylated hydroxytoluene(BHT)-terminated side chain,PTzBI-EHp-BTBHTx and N2200-BTBHTx(x=0.05,0.1,0.2),are designed and synthesized.It was found that incorporating appropriate ratio of benzothiadiazole(BT)with BHT side chains on the conjugated backbone would induce negligible effect on the molecular weight,absorption spectra and energy levels of polymers,however,which would obviously enhance the photostability of these polymers.Consequently,all-polymer solar cells(all-PSCs)and photodetectors were fabricated,and the all-PSC based on PTzBI-EHp-BTBHT0.05:N2200 realized an optimal power conversion efficiency(PCE)approaching~10%,outperforming the device based on pristine PTzBI-EHp:N2200.Impressively,the all-PSCs based on BHT-featuring terpolymers displayed alleviated PCEs degradation under continuous irradiation for 300 h due to the improved morphological and photostability of active layers.The OPDs based on BHT-featuring terpolymers achieved a lower dark current at−0.1 bias,which could be stabilized even after irradiation over 400 h.This study provides a feasible approach to develop terpolymers with antioxidant efficacy for improving the lifetime of OSCs and OPDs.
基金Partial support to this work by the Natural Sciences & Engineering Research Council of Canada (NSERC) is gratefully acknowledged
文摘ZnO nanoparticles are widely used for the electron transport layers(ETLs)of quantum dots light emitting devices(QLEDs).In this work we show that incorporating fluorine(F)into the ZnO ETL results in significant enhancement in device electroluminescence stability,leading to LT50 at 100 cd m^(−2) of 2,370,000 h in red QLED,47X longer than the control devices.X-ray photo-electron spectroscopy,time-of-flight secondary ion mass spectroscopy,photoluminescence and electrical measurements show that the F passivates oxygen vacancies and reduces electron traps in ZnO.Transient photoluminescence versus bias measurements and capacitance-voltage-luminance measurements reveal that the CF4 plasma-treated ETLs lead to increased electron concentration in the QD and the QD/hole transport layer interface,subsequently decreasing hole accumulation,and hence the higher stability.The findings provide new insights into the critical roles that optimizing charge distribution across the layers play in influencing stability and present a novel and simple approach for extending QLED lifetimes.
文摘Many new types of rolling mills have been studied and developed corresponding to the needs of improvement in productivity and quality.This presentation reflects back at some of the innovative technologies,which were developed by Mitsubishi-Hitachi Metals Machinery,Inc.(hereinafter referred to as M-H),including the evolution of the pair cross mill,mill stabilizing device,on-line roll profiler,shape meter for hot-rolling,endless hot-rolling, recent application of UCM,and M-H split housing type 20-high mill.
基金financially supported by the Central Guidance on Local Science and Technology Develop-ment Fund Project of Hebei Province(Grant No.226Z4306G)the Natural Science Foundation of Hebei Province(Grant No.F2023201005)+4 种基金the National Key Research and Development Program of China(Grant No.2017YFA0206600)the National Natural Science Foundation of China(Grant Nos.21922505,21773045)the CAS Instrument Develop-ment Project(Grant No.YJKYYQ20190010)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB36000000)CAS-NST Joint Research Projects(Grant No.163GJHZ2023017MI).
文摘Organic solar cells(OSCs)have attracted attention due to their lightweight nature,flexibility,and facile preparation using solution-based methods.Their efficiency has been further elevated by the rapid advancement of nonfullerene materials,achieving individual cell efficiencies that surpass 19%.Hence,the stability of nonfullerene solar cell production must be scrutinized.The stability of the cathode interface layer significantly impacts the overall stability of OSC devices.PFN-Br,a commonly employed cathode interface material,is susceptible to degradation due to its sensitivity to environmental humidity,consequently compromising the device stability.In this study,we introduce fluorescent dye molecules,rhodamine 101,as cathode interface layers in OSCs to establish device stability and assess their universality.A comparative investigation of rhodamine 101 and PFN-Br devices demonstrates the former’s distinct advantages in terms of thermal stability,photostability,and storage stability even without encapsulation,particularly in an inert environment.By employing the Kelvin probe,we compare the work function of different cathode interface films and reveal that the work function of the rhodamine 101 interface material remains relatively unaffected by environmental factors.As a consequence,the device performance stability is significantly enhanced.The application of such fluorescent dye molecules extends the scope of cathode interface layers,amplifies device stability,and propels industrialization.
基金the financial support from the Scientific Research Project of Education Department of Hunan Province(21C0091)the Open Fund of the State Key Laboratory of Luminescent Materials and Devices(South China University of Technology)(2023skllmd-13)+6 种基金the support from the National Natural Science Foundation of China(22209131,22005121)the open fund support from School of Materials Science and Engineering,Jiangsu Engineering Laboratory of Light-Electricity-Heat Energy-Converting Materials and Applications(GDRGCS2021002,GDRGCS2022003,GDRGCS2022002)the support from the National Key Research and Development Program of China(2022YFE0132400)the National Natural Science Foundation of China(21875182,52173023)the Key Scientific and Technological Innovation Team Project of Shaanxi Province(2020TD-002)111 Project 2.0(BP0618008)supported by the Director,Office of Science,Office of Basic Energy Sciences,of the U.S.Department of Energy(DE-AC0205CH11231)。
文摘Additives play a crucial role in enhancing the photovoltaic performance of polymer solar cells(PSCs).However,the typical additives used to optimize blend morphology of PSCs are still high boiling-point solvents,while their trace residues may reduce device stability.Herein,an effective strategy of“solidification of solvent additive(SSA)”has been developed to convert additive from liquid to solid,by introducing a covalent bond into low-cost solvent diphenyl sulfide(DPS)to synthesize solid dibenzothiophene(DBT)in one-step,which achieves optimized morphology thus promoting efficiency and device stability.Owing to the fine planarity and volatilization of DBT,the DBT-processed films achieve ordered molecular crystallinity and suitable phase separation compared to the additive-free or DPS-treated ones.Importantly,the DBT-processed device also possesses improved light absorption,enhanced charge transport,and thus a champion efficiency of 17.9%is achieved in the PM6:Y6-based PSCs with an excellent additive component tolerance,reproducibility,and stability.Additionally,the DBT-processed PM6:L8-BO-based PSCs are further fabricated to study the universality of SSA strategy,offering an impressive efficiency approaching19%as one of the highest values in binary PSCs.In conclusion,this article developed a promising strategy named SSA to boost efficiency and improve stability of PSCs.
基金supported by the National Natural Science Foun-dation of China(NSFC,52072207)Guizhou Provincial Science and Technology Projects(Grant Nos.ZK[2023]YB145,ZK[2023]YB149,and ZK[2022]214)+1 种基金Science and Technology Project of Guizhou Provincial Education Department(Grant Nos.[2022]143,[2022]150,and KY[2022]173)Science and Technology Foundation of Guizhou Minzu University(Grant Nos.GZMUZK[2022]YB21 and GZ-MUSYS[2021]02)。
文摘A self-powered ultraviolet photodetector(UV PD)with van der Waals(vdW)Schottky junction based on TiO_(2) nanorod arrays/Au-modulated V2 CTx MXene is reported.The Schottky junction enables the device to operate in self-powered mode.The dangling bond-free surface of V2 CTx MXene reduces the charge recombination at the junction interface.Meanwhile,V2 CTx MXene,with the work function(WF)increasing to 5.35 eV,forms a hole transport layer by contacting with Au electrode,which facilitates the carrier extraction.The electron lifetime in the device has prolonged to 8.95μs.As a result,the responsivity and detectivity of the PD have achieved 28 mA/W and 1.2×10^(11) cm Hz1/2/W(340 nm,65 mW/cm2,0 V),respectively.In addition,the presence of the Au electrode prevents the vanadium from coming into contact with oxygen and oxidizing,preserving the properties of the V2 CTx films.After 180 days of exposure to the atmosphere,the device performance remained at a particularly high level,indicating enhanced durability.This work points out an effective approach to modulate the properties of V2 CTx to obtain the high performance and stability of the UV PD.
基金Project supported by the 973 Program of China(No.2015CB932203)the National Natural Science Foundation of China(Nos.61377025,91433203)the Young 1000 Talents Global Recruitment Program of China
文摘Perovskite solar cells have experienced an unprecedented rapid development in the power conversion efficiency（PCE）during the past 7 years,and the record PCE has been already comparable to the traditional polycrystalline silicon solar cells.Presently,it is more urgent to address the challenge on device stability for the future commercial application.Recently,the inorganic cesium lead halide perovskite has been intensively studied as one of the alternative candidates to improve device stability through controlling the phase transition.The cesium（Cs）-doped perovskites show more superior stability comparing with organic methylammonium（MA）lead halide perovskite or formamidinium（FA）lead halide perovskite.Here,recent progress of the inorganic cesium application in organic-inorganic perovskite solar cells（PSCs）is highlighted from the viewpoints of the device efficiency and the device stability.
文摘Highly efficient and stable polymer solar cells （PSCs） have been fabricated by adopting solution-derived hybrid poly（ethylene glycol）-titanium oxide （PEG-TiOx） nanocomposite films as a novel and universal cathode buffer layer （CBL）, which can greatly improve device performance by reducing interface energy barriers and enhancing charge extraction/collection. The performance of inverted PSCs with varied bulk-heterojunctions （BHJs） based on this hybrid nanocomposite CBL was found to be much better than those of control devices with a pure TiOx CBL or without a CBL. An excellent power conversion efficiency up to 9.05% under AM 1.5G irradiation （100 mW-cm^-2） was demonstrated, which represents a record high value for inverted PSCs with TiOx-based interface materials.
基金supported by the National Key R&D Program of China(2016YFB0400701)NSFC-Guangdong Joint Program(U1301243)+1 种基金the National Basic Research Program of China(2015CB655000)support of Dongguan Major Special Project(2017215117010)
文摘There has been an increasing demand for high-performance and cost-effective organic electron-transport materials for organic light-emitting diodes （OLEDs）. In this contribution, we present a simple compound 3-（3-（4,6-diphenyl-l,3,5-triazin-2-yl）phenyl）-1,10-phenanthroline through the facile Pd-catalyzed coupling of a triphenyltriazine boronic ester with 3-hromo-1,10-phenanthroline. It shows a high Tg of 112℃. The ultraviolet photoelectron spectroscopy measurements reveal a deep HOMO level of -6.5 eV. The LUMO level is derived as -3.0 eV, based on the optical bandgap. The low-temperature solid-state phosphorescent spectrum gives a triplet energy of -2.36eV. n-Doping with 8-hydroxyquinolatolithium （Liq, 1：1） leads to considerably improved electron mobility of 5.2 × 10 -6 -5.8 × 10 -5 cm2 v-1 S-1 at E=（2-5） × 10 5Vcm -1, in contrast with the triarylphosphine oxide- phenantroline molecular conjugate we reported previously. It has been shown that through optimizing the device structure and hence suppressing polaron-exciton annihilation, introducing this single Liq-doped electron-transport layer could offer high-efficiency and stable phosphorescent OLEDs.
基金supported by grants from the National Basic Research Program of China(no.2014CB643505)the Natural Science Foundation of Jilin Province,China(no.20170101169JC)+2 种基金the Open Project of the State Key Laboratory of Supramolecular Structure and Materials(no.sklssm202043)the Graduate Innovation Fund of Jilin University(no.101832020CX339)W.L.and C.Z.acknowledge the support from the Jiangxi Provincial Department of Science and Technology(nos.20192ACB20009 and 20192BBEL50026).
文摘An alcohol-soluble,environmentally friendly,and low-cost surfactant-encapsulated polyoxometalate complex[(C8H17)4N]4[SiW_(12)O40](TOASiW_(12))as a cathode interlayer(CIL)has exhibited excellent universality for various active layers and cathodes in nonfullerene polymer solar cells(NF-PSCs).In particular,incorporating TOASiW_(12) as the CIL enhanced power conversion efficiencies(PCEs)of the PM6:Y6-based NF-PSCs with Al or Ag cathode to 16.14%and 15.89%,respectively,and the PCEs of PM6:BTP-BO4Cl-based NF-PSCs with Al or Ag cathode to 17.04%and 17.00%,respectively.More importantly,the performances of the devices with TOASiW_(12) were insensitive to the TOASiW_(12) thickness from 3 to 33 nm.Furthermore,the NF-PSCs with TOASiW_(12) exhibited better device stability.Combined characterization of the photocurrent density versus effective voltage,capacitance versus voltage and electron mobility demonstrated that TOASiW_(12) as the CIL effectively promoted exciton dissociation,charge-carrier extraction,built-in potential,charge-carrier density,and electron mobility in the NF-PSCs.These findings suggest that TOASiW_(12) is a promising,competitive CIL for NF-PSCs fabricated by roll-to-roll processing.
基金The authors acknowledge the financial support from the National Key Research and Development Program of China(no.2019YFA0705900)funded by MOSTthe Youth Innovation Promotion Association CAS(no.2018037)+1 种基金the National Natural Science Foundation of China(no.21875263)the Basic and Applied Basic Research Major Program of Guangdong Province(no.2019B030302007).
文摘Although the photovoltaic efficiency of organic solar cells(OSCs)has exceeded 17%,poor lifetime excludes OSCs from practical use.In particular,UV rays in sunlight may cause the decomposition of organic photovoltaic materials,which has been proved to be the main reason for the efficiency decay.At present,there is still no effective approach to substantially improve the device stability.Herein,we fabricate a highly efficient OSC with exceptional stability under sunlight illumination by incorporating a UV-resistant cathode interlayer(CIL),namely(sulfobetaine-N,Ndimethylamino)propyl naphthalene diimide(NDI-B).NDI-B was designed and synthesized based on the naphthalene diimide(NDI)unit,thereby exhibiting excellent capability of electron collection.Moreover,NDI-B shows strong absorption in the UV region and has good UV resistance.Devices using NDI-B as a CIL exhibited a photovoltaic efficiency of 17.2%,representing the state-of-the-art photovoltaic performance of OSCs.Notably,the NDI-B-modified OSC exhibited a T80 of over 1800 h under full-sun AM 1.5 G illumination(100 mW cm^(−2)),which represents the best stability for OSCs.We demonstrate that the unique ability of the NDI-B interlayer to convert UV light to an additional photocurrent can effectively protect photovoltaic materials from UV-induced decomposition,which is the key to obtain high OSC stability under operational conditions.
基金the National Natural Science Foundation of China(NSFC)(51773157 and 52061135206)the Fundamental Research Funds for the Central UniversitiesThe authors also thank the support of the opening project of Key Laboratory of Materials Processing and Mold and Beijing National Laboratory for Molecular Sciences(BNLMS201905).
文摘Clusters of water molecules have low ionization energies because of stabilization of charge from the dipole moment of surrounding molecules,and thus can form potential traps resulting in the undesirable photovoltaic performance in organic solar cells(OSCs).Herein,we demonstrated a solvent-water evaporation(SWE)strategy,which can effectively remove the water-induced traps that are omnipresent in photoactive layers,leading to a significant improvement in device performance.A higher power conversion efficiency of 17.10%and a better device photostability are achieved by using this SWE method,as compared with the untreated binary PM6:Y6 system(15.83%).We highlight the water-related traps as a limiting factor for carrier transport and extraction properties,and further reveal the good universality of the SWE strategy applied into OSCs.In addition,organic light-emitting diodes and organic field-effect transistors are investigated to demonstrate the applicability of this SWE approach.This strategy presents a major step forward for advancing the field of organic electronics.
基金supported by the National Natural Science Foundation of China(51903189,51800334)。
文摘Interfacial regulation,serving multiple roles,is critical for the fabrication of stable and efficient organic photovoltaics(OPVs).Herein,a multifunctional cathode interlayer PDINO(15 nm)is prepared by regulating film thickness,which is inserted between active components and stable silver electrode to align work function,and maintain good interfacial contact and device stability.The thick film can help to reduce interfacial surface defects,keep stable surface morphology,and block the silver diffusion into the active layer.Consequently,the optimal PM6:Y6 device records an impressive power conversion efficiency(PCE)of 17.48%with minimized non-radiative recombination loss of 0.239 V.More importantly,the unencapsulated device maintains 91%of the original PCE after aging for over 60 days at 25℃ and 10%relative humidity in dark conditions.Meanwhile,the PM6:eC9 device achieves a remarkable PCE of 18.22%with the enhancement of open-circuit voltage(V_(oc)).Furthermore,the 1 cm^(2) device-based PDINO(15 nm)/Ag shows a high PCE of 15.2%while only 12.6%for PDINO(9 nm)/Al,indicating the good compatibility of PDINO(15 nm)interlayer with the R2R coating processes used in large-area OPVs fabrication.This work highlights the promise of interfacial regulation to simultaneously stabilize and enhance the efficiency of organic photovoltaics.
