Scalable fabrication of efficient wide-bandgap(WBG)perovskite solar cells(PSCs)is crucial to realize the full commercial potential of tandem solar cells.However,there are challenges in fabricating efficient methylammo...Scalable fabrication of efficient wide-bandgap(WBG)perovskite solar cells(PSCs)is crucial to realize the full commercial potential of tandem solar cells.However,there are challenges in fabricating efficient methylammonium-free(MA-free)WBG PSCs by blade coating,especially its phase separation and films stability.In this work,an MA-free WBG perovskite ink is developed for preparing FA_(0.8)Cs_(0.2)Pb(I_(0.75)Br_(0.25))_(3)films by blade coating in ambient air.Among various A-site iodides,RbI is found to be the most effective in suppressing the precipitation of PbI_(2)induced by Pb(SCN)_(2)while keeping the enlarged grains.The distribution of Rb suggested that the Rb ions are kept isolated with the perovskite grains during the crystallization and Ostwald ripening processes,which contributes to the formation of the large-grain WBG perovskite film with minimum non-radiative recombination.As a result,a power conversion efficiency(PCE)of 23.0%was achieved on small-area WBG PSCs,while mini-modules with an aperture area of 10.5 cm^(2)exhibited a PCE of 20.2%,among the highest reported for solar cells prepared with WBG perovskites via blade coating.This work presents a scalable and reproducible fabrication strategy for stable MA-free WBG PSCs under ambient conditions,advancing their path toward commercialization.展开更多
Thin films of perovskite deposited from solution inevitably introduce large number of defects,which serve as recombination centers and are detrimental for solar cell performance.Although many small molecules and polym...Thin films of perovskite deposited from solution inevitably introduce large number of defects,which serve as recombination centers and are detrimental for solar cell performance.Although many small molecules and polymers have been delicately designed to migrate defects of perovskite films,exploiting credible passivation agents based on natural materials would offer an alternative approach.Here,an ecofriendly and cost-effective biomaterial,ploy-L-lysine(PLL),is identified to effectively passivate the defects of perovskite films prepared by blade-coating.It is found that incorporation of a small amount(2.5 mg mL^(-1))of PLL significantly boosts the performance of printed devices,yielding a high efficiency of 19.45% with an increase in open-circuit voltage by up to 100 mV.Density functional theory calculations combined with X-ray photoelectron spectroscopy reveal that the functional groups(-NH2,-COOH)of PLL effectively migrate the Pb-I antisite defects via Pb-N coordination and suppress the formation of metallic Pb in the blade-coated perovskite film.This work suggests a viable avenue to exploit passivation agents from natural materials for preparation of high-quality perovskite layers for optoelectronic applications.展开更多
Flexible transparent conductive films were made on PET substrates by spin and blade coating, using graphene sheets dispersed in PEDOT : PSS solution. Ultrasonic substrate vibration was used to improve microstructure a...Flexible transparent conductive films were made on PET substrates by spin and blade coating, using graphene sheets dispersed in PEDOT : PSS solution. Ultrasonic substrate vibration was used to improve microstructure and properties of the films. Comparing to the pristine PEDOT : PSS film, the sheet resistance is 3 to 4 orders of magnitude lower with the addition of graphene. The conductivity and reproducibility of the film are improved for two-layer films comparing to one-layer films, with a reduction in transparency. Films prepared with substrate vibration showed lower sheet resistance for one-layer films, as the size of dewetting areas is reduced. In addition, large-area flexible films with desirable conductivity and transmittance were successfully fabricated by blade coating, which is promising, as the process is low-cost, scalable and compatible with roll-to-roll manufacturing.展开更多
Controlling the orientation of two-dimensional MXene within layered films is essential to optimize or tune their mechanical properties and electromagnetic interference shielding(EMI)performance,but achieving the high ...Controlling the orientation of two-dimensional MXene within layered films is essential to optimize or tune their mechanical properties and electromagnetic interference shielding(EMI)performance,but achieving the high orientation MXene layers on an industrial scale remains a challenging goal.In this paper,a scalable layer-by-layer blade coating(LbLBC)method was employed to fabricate highly oriented MXene/polyvinyl alcohol(PVA)films.During the LbLBC process,MXene/PVA colloid suffered a strong shearing effect,which induced the ordered alignment of MXene nanosheets along the direction of the blade movement.The orientation of MXene can be effectively adjusted by changing the scraping gap of LbLBC,achieving a maximum Herman orientation factor f of 0.81.As a result,the mechanical properties and EMI performance of the as-prepared MXene/PVA films are in direct proportion to their orientation,with the optimal values of tensile strength of 145.5 MPa,fracture strain of 19.6%,toughness of 17.7 MJ·m^(−3),and EMI shielding effectiveness of 36.7 dB.Furthermore,the inherently low mid-infrared(mid-IR)emissivity of MXene,combined with the densely oriented structure affords the composite films with IR stealth,resulting in a substantial decrease from 150 to 66.1℃in the radiative temperature of a surface.Conclusively,these scalable MXene/PVA films exhibit remarkable potential for integration into the next generation of multifunctional protective camouflage materials.展开更多
A novel NiAlTa blade tip protective coating is designed and its oxidation,hot corrosion,and interdiffusion with DD5 single-crystal superalloys are investigated.NiAlTa coatings exhibit low oxidation rates.The dragging ...A novel NiAlTa blade tip protective coating is designed and its oxidation,hot corrosion,and interdiffusion with DD5 single-crystal superalloys are investigated.NiAlTa coatings exhibit low oxidation rates.The dragging effect of Ta on Al hinders the external diffusion of Al.Ta that accumulates at the Al_(2)O_(3)grain boundaries reduces the internal diffusion of O by combining or reacting with it.NaCl aggravates the hot corrosion through self ustaining cycles of chlorination/oxidation.β-NiAl phase fails first as a diffusion channel for the corrosive medium.Significant element interdiffusion occurs.An interdiffusion zone and a secondary reaction zone are formed.Interdiffusion changes the percentage of elements,causing a phase transition of the coating.The volume change caused by the phase transition induces bulging and cracking of the oxide film.Furthermore,the oxidation,hot corrosion,and interdiffusion mechanisms are discussed.展开更多
Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating method.In this work,we found these two pre-crystallization proces...Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating method.In this work,we found these two pre-crystallization processes lead to different order of crystallization dynamics within the perovskite thin film,resulting in the differences of additive distribution.We then tailor-designed an additive molecule named 1,3-bis(4-methoxyphenyl)thiourea to obtain films with fewer defects and holes at the buried interface,and prepared perovskite solar cells with a certified efficiency of 23.75%.Furthermore,this work also demonstrates an efficiency of 20.18%for the large-area perovskite solar module(PSM)with an aperture area of 60.84 cm^(2).The PSM possesses remarkable continuous operation stability for maximum power point tracking of T_(90)>1000 h in ambient air.展开更多
A two-dimensional transition metal carbide/nitride/carbonitride(MXene)and waterborne polyurethane(WPU)were uniformly mixed to form an MXene/WPU coating,which was loaded on polyethylene terephthalate(PET)fabric through...A two-dimensional transition metal carbide/nitride/carbonitride(MXene)and waterborne polyurethane(WPU)were uniformly mixed to form an MXene/WPU coating,which was loaded on polyethylene terephthalate(PET)fabric through blade coating to prepare an MXene/WPU@PET composite fabric with electromagnetic shielding properties.The micro-morphology and composition,surface wettability,tensile properties,electrical conductivity,and electromagnetic shielding properties of the composite fabric were studied.The results showed that the MXene/WPU@PET composite fabric exhibited the cha-racteristics of flexibility and firmness,and a unit area load capacity of MXene/WPU was 1.9 mg/cm^(2),the conductivity 760 S/m,and the electromagnetic shielding effectiveness up to 42 dB(8.2-12.4 GHz);and this convenient and effective method can be used to prepare lightweight and flexible electromagnetic shielding materials,promising broad application prospects in the field of wearable products.展开更多
Currently,perovskite solar cells have achieved commendable progresses in power conversion efficiency(PCE)and operational stability.However,some conventional laboratory-scale fabrication methods become challenging when...Currently,perovskite solar cells have achieved commendable progresses in power conversion efficiency(PCE)and operational stability.However,some conventional laboratory-scale fabrication methods become challenging when scaling up material syntheses or device production.Particularly,the prolonged high-temperature annealing process for the crystallization of perovskites requires a substantial amount of energy consumption and impact the modules’throughput.Here,we report a modified near-infrared annealing(NIRA)process,which involves the excess PbI_(2)engineered crystallization,efficiently reduces the preparation time for perovskite active layer to within 20 s compared to dozens of min in conventional hot plate annealing(HPA)process.The study showed that the incorporated PbI_(2)promoted the consistent nucleation of the perovskite film,leading to the subsequent rapid and homogeneous crystallization at the NIRA stage.Thus,highly crystalized perovskite film was realized with even better crystallization performance than conventional HPA-based film.Ultimately,efficient perovskite solar modules of 36 and 100 cm^(2)were readily fabricated with the optimal PCEs of 22.03%and 20.18%,respectively.This study demonstrates,for the first time,the successful achievement of homogeneous and high-quality crystallization in large-area perovskite films through rapid NIRA processing.This approach not only significantly reduces energy consumption during production,but also substantially shortens the manufacturing cycle,paving a new path toward the commercial-scale application of perovskite solar modules.展开更多
The extreme instability of pureα-phase FAPbI_(3) under high humidity conditions restricts the highthroughput fabrication in unmodified air environments,resulting in poor performance ofα-phase FAPbI_(3) perovskite de...The extreme instability of pureα-phase FAPbI_(3) under high humidity conditions restricts the highthroughput fabrication in unmodified air environments,resulting in poor performance ofα-phase FAPbI_(3) perovskite devices obtained by scalable fabrication methods.Here we synthesized hyperbranched copper phthalocyanine(HCuPc)as a supramolecular additive with twisted phthalocyanine units to realize the molecular-level encapsulation at the grain boundaries through supramolecular interaction,which greatly broadened the processing window of FAPbI_(3) under high humidity.At the same time,unlike traditional encapsulation layer that carrier can only be collected by tunneling effect,the twisted phthalocyanine ring of HCu Pc in perovskite films is more conducive to hole extraction.Finally,a record efficiency was achieved in pure FAPbI_(3) based inverted structured solar cell by blade-coating to the best of our knowledge,even under unmodified humid air conditions(relative humidity of 65%–85%).The best operational stability of 3D pure FAPbI_(3) devices can also be achieved at the same time and unencapsulated HCuPc-FAPbI_(3) device can even operate with negligible degradation for 100 h in the open air(RH 30%–40%).展开更多
Infrared solar cells are more efective than normal bandgap solar cells at reducing the spectral loss in the near-infrared region,thus also at broadening the absorption spectra and improving power conversion efciency.P...Infrared solar cells are more efective than normal bandgap solar cells at reducing the spectral loss in the near-infrared region,thus also at broadening the absorption spectra and improving power conversion efciency.PbS colloidal quantum dots(QDs)with tunable bandgap are ideal infrared photovoltaic materials.However,QD solar cell production sufers from small-areabased spin-coating fabrication methods and unstable QD ink.Herein,the QD ink stability mechanism was fully investigated according to Lewis acid–base theory and colloid stability theory.We further studied a mixed solvent system using dimethylformamide and butylamine,compatible with the scalable manufacture of method-blade coating.Based on the ink system,100 cm2 of uniform and dense near-infrared PbS QDs(~0.96 eV)flm was successfully prepared by blade coating.The average efciencies of above absorber-based devices reached 11.14%under AM1.5G illumination,and the 800 nm-fltered efciency achieved 4.28%.Both were the top values among blade coating method based devices.The newly developed ink showed excellent stability,and the device performance based on the ink stored for 7 h was similar to that of fresh ink.The matched solvent system for stable PbS QD ink represents a crucial step toward large area blade coating photoelectric devices.展开更多
A rotating cantilever sandwich-plate model with a pre-twisted and pre-set angle has been developed to investigate the vibrational behavior of an aero-engine turbine blade with thermal barrier coating(TBC) layers. The ...A rotating cantilever sandwich-plate model with a pre-twisted and pre-set angle has been developed to investigate the vibrational behavior of an aero-engine turbine blade with thermal barrier coating(TBC) layers. The classic von Karman plate theory and the first-order shear deformation theory are applied to derive the energy equations of the rotating TBC blade, in which the geometric shapes, the work ambient temperature, and the TBC material properties are considered. The Chebyshev-Ritz method is used to obtain the nature frequency of the rotating TBC blade. For static frequency and modal analysis, the finite-element method(FEM)is also applied to compare and validate the results from the Chebyshev-Ritz method. A good agreement is found among these kinds of methods. For dynamic frequency, the results are analyzed in detail concerning the influence of system parameters such as the thickness of the TBC layer, the working temperature, and the pre-twisted and pre-set angle. Finally, the Campbell diagram is demonstrated to analyze the resonance property of the cantilever sandwich TBC blade model.展开更多
A hot wind tunnel of annular cascade test rig is established for measuring temperature distribution on a real gas turbine blade surface with infrared camera.Besides,conjugate heat transfer numerical simulation is perf...A hot wind tunnel of annular cascade test rig is established for measuring temperature distribution on a real gas turbine blade surface with infrared camera.Besides,conjugate heat transfer numerical simulation is performed to obtain cooling efficiency distribution on both blade substrate surface and coating surface for comparison.The effect of thermal barrier coating on the overall cooling performance for blades is compared under varied mass flow rate of coolant,and spatial difference is also discussed.Results indicate that the cooling efficiency in the leading edge and trailing edge areas of the blade is the lowest.The cooling performance is not only influenced by the internal cooling structures layout inside the blade but also by the flow condition of the mainstream in the external cascade path.Thermal barrier effects of the coating vary at different regions of the blade surface,where higher internal cooling performance exists,more effective the thermal barrier will be,which means the thermal protection effect of coatings is remarkable in these regions.At the designed mass flow ratio condition,the cooling efficiency on the pressure side varies by 0.13 for the coating surface and substrate surface,while this value is 0.09 on the suction side.展开更多
The solid-phase microextraction technique quantifies analytes without considerably affecting the sample composition.Herein,a proof-of-concept study was conducted to demonstrate the use of coated probe electrospray ion...The solid-phase microextraction technique quantifies analytes without considerably affecting the sample composition.Herein,a proof-of-concept study was conducted to demonstrate the use of coated probe electrospray ionization(coated-PESI)and coated blade spray(CBS)as ambient mass spectrometry approaches for monitoring drug biotransformation.The ability of these methods was investigated for monitoring the dephosphorylation of a prodrug,combretastatin A4 phosphate(CA4P),into its active form,combretastatin A4(CA4),in a cell culture medium supplemented with fetal bovine serum.The CBS spot analysis was modified to achieve the same extraction efficiency as protein precipitation and obtained results in 7 min.Because coated-PESI performs extraction without consuming any samples,it is the preferred technique in the case of a limited sample volume.Although coated-PESI only extracts small quantities of analytes,it uses the desorption solvent volume of 5-10 pL,resulting in high sensitivity,thus allowing the detection of compounds after only 1 min of extraction.The biotransformation of CA4P into CA4 via phosphatases occurs within the simple matrix,and the proposed sample preparation techniques are suitable for monitoring the biotransformation.展开更多
The direct coupling of solid-phase microextraction(SPME)to mass spectrometry(MS)(SPME-MS)has proven to be an effective method for the fast screening and quantitative analysis of compounds in complex matrices such as b...The direct coupling of solid-phase microextraction(SPME)to mass spectrometry(MS)(SPME-MS)has proven to be an effective method for the fast screening and quantitative analysis of compounds in complex matrices such as blood and plasma.In recent years,our lab has developed three novel SPME-MS techniques:SPME-microfluidic open interface-MS(SPME-MOI-MS),coated blade spray-MS(CBS-MS),and SPME-probe electrospray ionization-MS(SPME-PESI-MS).The fast and high-throughput nature of these SPME-MS technologies makes them attractive options for point-of-care analysis and anti-doping testing.However,all these three techniques utilize different SPME geometries and were tested with different MS instruments.Lack of comparative data makes it difficult to determine which of these methodologies is the best option for any given application.This work fills this gap by making a comprehensive comparison of these three technologies with different SPME devices including SPME fibers,CBS blades,and SPME-PESI probes and SPME-liquid chromatography-MS(SPME-LC-MS)for the analysis of drugs of abuse using the same MS instrument.Furthermore,for the first time,we developed different desorption chambers for MOI-MS for coupling with SPME fibers,CBS blades,and SPME-PESI probes,thus illustrating the universality of this approach.In total,eight analytical methods were developed,with the experimental data showing that all the SPME-based methods provided good analytical performance with R^(2)of linearities larger than 0.9925,accuracies between 81%and 118%,and good precision with an RSD%≤13%.展开更多
Fully printed perovskite solar cells(PSCs)were fabricated in air with all constituent layers,except for electrodes,deposited by the blade coating technique.The PSCs incorporated,for the first time,a nanometer-thick pr...Fully printed perovskite solar cells(PSCs)were fabricated in air with all constituent layers,except for electrodes,deposited by the blade coating technique.The PSCs incorporated,for the first time,a nanometer-thick printed bathocuproine(BCP)hole blocking buffer using blade coating and deposited at relative humidity up to 50%.The PSCs with a p-i-n structure(glass/indium tin oxide(ITO)/poly(3,4-ethylenedioxythiophene)polystyrene sulfonate(PEDOT:PSS)/CH_(3)NH_(3)Pbl_(3)/[6,6]-phenyl-C_(61)-butyric acid methyl ester(PCBM)/BCP/Ag)delivered a maximum power conversion efficiency(PCE)of 14.9%on an active area of 0.5 cm^(2)when measured under standard test conditions.The PSCs with a blade coated BCP delivered performance of 10%and 63%higher(in relative terms)than those incorporating a spin coated BCP or without any BCP film,respectively.The atomic force microscopy(AFM)showed that blade coated films were more homogeneous and acted also as a surface planarizer leading to a reduction of roughness which improved BCP/Ag interface lowering charge recombination.The demonstration of 15%efficient devices with all constituent layers,including nanometer-thick BCP(〜10 nm),deposited by blade coating in air,demonstrates a route for industrialization of this technology.展开更多
Achieving high-performance perovskite solar modules(pero-SMs)over large areas under ambient conditions remains a significant barrier to the commercialization of perovskite photovoltaics.This challenge arises from the ...Achieving high-performance perovskite solar modules(pero-SMs)over large areas under ambient conditions remains a significant barrier to the commercialization of perovskite photovoltaics.This challenge arises from the strong solvent-perovskite coordination interactions in the hygroscopic perovskite precursor ink,which complicate the control of nucleation-growth kinetics and phase evolution during film formation in the presence of moisture,thereby hindering the formation of high-quality perovskite films.In this work,a“vip-solvent”additive strategy was developed by incorporating N,N-dimethylthioformamide(DMT)into the perovskite precursor ink to effectively modulate the coordination between the solvent and perovskite.It is demonstrated that DMT,structurally similar to the“main-solvent”system(DMF and DMSO),possesses lower coordination ability with Pb2+and forms non-covalent interactions with the primary solvents.These interactions weaken the solvent-perovskite coordination without sacrificing solubility,thereby stabilizing homogeneous nucleation and promoting direct crystallization from the sol-gel phase toα-FAPbI3.As a result,the ambient-printed FAPbI3 films exhibited high quality,with more compact grain stacking,smoother morphology,higher phase purity,and fewer defects.Consequently,the resulting perovskite solar cells(0.062 cm2)and pero-SMs(15.64 cm2)fabricated via blade coating under ambient conditions achieved remarkable power conversion efficiencies(PCEs)of 24.46%and 22.54%,respectively.展开更多
Large pinhole-free,high-crystal-quality per-ovskite films are the key to realizing efficient,stable CsPbI_(3)perovskite modules.In this work,we use the crystal growth modulation strategy to prepare high-quality CsPbI_...Large pinhole-free,high-crystal-quality per-ovskite films are the key to realizing efficient,stable CsPbI_(3)perovskite modules.In this work,we use the crystal growth modulation strategy to prepare high-quality CsPbI_(3)films from small to large sizes using a new precursor solution with CsI/DMAPbI_(3)/PbI_(2)in a DMAAc/DMF mixed solvent(DMAAc:dimethylamine acetate).The champion small-size CsPbI_(3)de-vice presents a photoelectric conversion efficiency(PCE)above 21%and a certified PCE of 20.05%,and the best blade-coated CsPbI_(3)minimodule exhibits a PCE of 18.3%for an aperture area of 12.39 cm2 and a PCE of 19.9%for an active area of 11.40 cm^(2).In addition,the composition engineering of the precursor solution toward CsPbI_(3)crystallization is explored:the DMAAc/DMF mixed solvent can facilitate phase trans-formation and reduce the nucleation rate,and the mixture of PbI2 and DMAPbI3 will further improve the film micro-structure and uniformity.Consequently,the anti-humidity stability and phase stability of the CsPbI_(3)films are greatly improved,and the corresponding devices exhibit good op-erational stability.CsPbI_(3)modules with simple encapsulation also present excellent long-term storage stability over 150 days.This crystal growth regulation strategy provides a new method to produce large-scale CsPbI_(3)and even hybrid per-ovskite solar cells for future commercialization.展开更多
基金supported by the National Natural Science Foundation of China(No.62204211)the Australian Research Council(ARC)Discovery Early Career Researcher Award Fellowship(DE230100163)+1 种基金support of the Henry Royce Institute for Advanced Materials through the Industrial Collaboration Programme and MATcelerateZero(EPSRC Grant EP/X527257/1)support for the NEXTCCUS project(Project ID:327327)from the Department for Energy Security and Net Zero,the ACT program,and Horizon 2020(Project No.691712).
文摘Scalable fabrication of efficient wide-bandgap(WBG)perovskite solar cells(PSCs)is crucial to realize the full commercial potential of tandem solar cells.However,there are challenges in fabricating efficient methylammonium-free(MA-free)WBG PSCs by blade coating,especially its phase separation and films stability.In this work,an MA-free WBG perovskite ink is developed for preparing FA_(0.8)Cs_(0.2)Pb(I_(0.75)Br_(0.25))_(3)films by blade coating in ambient air.Among various A-site iodides,RbI is found to be the most effective in suppressing the precipitation of PbI_(2)induced by Pb(SCN)_(2)while keeping the enlarged grains.The distribution of Rb suggested that the Rb ions are kept isolated with the perovskite grains during the crystallization and Ostwald ripening processes,which contributes to the formation of the large-grain WBG perovskite film with minimum non-radiative recombination.As a result,a power conversion efficiency(PCE)of 23.0%was achieved on small-area WBG PSCs,while mini-modules with an aperture area of 10.5 cm^(2)exhibited a PCE of 20.2%,among the highest reported for solar cells prepared with WBG perovskites via blade coating.This work presents a scalable and reproducible fabrication strategy for stable MA-free WBG PSCs under ambient conditions,advancing their path toward commercialization.
基金supported by the National Natural Science Foundation of China(Grant No.61705090,11804117)Natural Science Foundation of Guangdong Province(2020A1515010853)。
文摘Thin films of perovskite deposited from solution inevitably introduce large number of defects,which serve as recombination centers and are detrimental for solar cell performance.Although many small molecules and polymers have been delicately designed to migrate defects of perovskite films,exploiting credible passivation agents based on natural materials would offer an alternative approach.Here,an ecofriendly and cost-effective biomaterial,ploy-L-lysine(PLL),is identified to effectively passivate the defects of perovskite films prepared by blade-coating.It is found that incorporation of a small amount(2.5 mg mL^(-1))of PLL significantly boosts the performance of printed devices,yielding a high efficiency of 19.45% with an increase in open-circuit voltage by up to 100 mV.Density functional theory calculations combined with X-ray photoelectron spectroscopy reveal that the functional groups(-NH2,-COOH)of PLL effectively migrate the Pb-I antisite defects via Pb-N coordination and suppress the formation of metallic Pb in the blade-coated perovskite film.This work suggests a viable avenue to exploit passivation agents from natural materials for preparation of high-quality perovskite layers for optoelectronic applications.
基金the Technology Development Project supported by SAPOthe Shanghai Sailing(YANG FAN)Program(No.16YF1406200)+1 种基金the Oriental Scholar Fund Supported by Shanghai Municipal Education Commissionthe Funding from the National Natural Science Foundation of China(NSFC)
文摘Flexible transparent conductive films were made on PET substrates by spin and blade coating, using graphene sheets dispersed in PEDOT : PSS solution. Ultrasonic substrate vibration was used to improve microstructure and properties of the films. Comparing to the pristine PEDOT : PSS film, the sheet resistance is 3 to 4 orders of magnitude lower with the addition of graphene. The conductivity and reproducibility of the film are improved for two-layer films comparing to one-layer films, with a reduction in transparency. Films prepared with substrate vibration showed lower sheet resistance for one-layer films, as the size of dewetting areas is reduced. In addition, large-area flexible films with desirable conductivity and transmittance were successfully fabricated by blade coating, which is promising, as the process is low-cost, scalable and compatible with roll-to-roll manufacturing.
基金the National Natural Science Foundation of China(Nos.52273085,52303113,and 12072325)the Natural Science Foundation of China of Henan Province(No.222300420541)the Key Scientific Research Projects of Colleges and Universities in Henan Province,China(No.24A430045).
文摘Controlling the orientation of two-dimensional MXene within layered films is essential to optimize or tune their mechanical properties and electromagnetic interference shielding(EMI)performance,but achieving the high orientation MXene layers on an industrial scale remains a challenging goal.In this paper,a scalable layer-by-layer blade coating(LbLBC)method was employed to fabricate highly oriented MXene/polyvinyl alcohol(PVA)films.During the LbLBC process,MXene/PVA colloid suffered a strong shearing effect,which induced the ordered alignment of MXene nanosheets along the direction of the blade movement.The orientation of MXene can be effectively adjusted by changing the scraping gap of LbLBC,achieving a maximum Herman orientation factor f of 0.81.As a result,the mechanical properties and EMI performance of the as-prepared MXene/PVA films are in direct proportion to their orientation,with the optimal values of tensile strength of 145.5 MPa,fracture strain of 19.6%,toughness of 17.7 MJ·m^(−3),and EMI shielding effectiveness of 36.7 dB.Furthermore,the inherently low mid-infrared(mid-IR)emissivity of MXene,combined with the densely oriented structure affords the composite films with IR stealth,resulting in a substantial decrease from 150 to 66.1℃in the radiative temperature of a surface.Conclusively,these scalable MXene/PVA films exhibit remarkable potential for integration into the next generation of multifunctional protective camouflage materials.
基金financially supported by the Strategic Priority Research Program of the Chinese Academy of Sciences,Grant(No.XDB 047010204)Liaoning Key Laboratory of Aero-engine Material Tribology for both financial and facility support
文摘A novel NiAlTa blade tip protective coating is designed and its oxidation,hot corrosion,and interdiffusion with DD5 single-crystal superalloys are investigated.NiAlTa coatings exhibit low oxidation rates.The dragging effect of Ta on Al hinders the external diffusion of Al.Ta that accumulates at the Al_(2)O_(3)grain boundaries reduces the internal diffusion of O by combining or reacting with it.NaCl aggravates the hot corrosion through self ustaining cycles of chlorination/oxidation.β-NiAl phase fails first as a diffusion channel for the corrosive medium.Significant element interdiffusion occurs.An interdiffusion zone and a secondary reaction zone are formed.Interdiffusion changes the percentage of elements,causing a phase transition of the coating.The volume change caused by the phase transition induces bulging and cracking of the oxide film.Furthermore,the oxidation,hot corrosion,and interdiffusion mechanisms are discussed.
基金supported by National Natural Science Foundation of China(62104082)Guangdong Basic and Applied Basic Research Foundation(2022A1515010746,2022A1515011228,and 2022B1515120006)the Science and Technology Program of Guangzhou(202201010458).
文摘Gas quenching and vacuum quenching process are widely applied to accelerate solvent volatilization to induce nucleation of perovskites in blade-coating method.In this work,we found these two pre-crystallization processes lead to different order of crystallization dynamics within the perovskite thin film,resulting in the differences of additive distribution.We then tailor-designed an additive molecule named 1,3-bis(4-methoxyphenyl)thiourea to obtain films with fewer defects and holes at the buried interface,and prepared perovskite solar cells with a certified efficiency of 23.75%.Furthermore,this work also demonstrates an efficiency of 20.18%for the large-area perovskite solar module(PSM)with an aperture area of 60.84 cm^(2).The PSM possesses remarkable continuous operation stability for maximum power point tracking of T_(90)>1000 h in ambient air.
文摘A two-dimensional transition metal carbide/nitride/carbonitride(MXene)and waterborne polyurethane(WPU)were uniformly mixed to form an MXene/WPU coating,which was loaded on polyethylene terephthalate(PET)fabric through blade coating to prepare an MXene/WPU@PET composite fabric with electromagnetic shielding properties.The micro-morphology and composition,surface wettability,tensile properties,electrical conductivity,and electromagnetic shielding properties of the composite fabric were studied.The results showed that the MXene/WPU@PET composite fabric exhibited the cha-racteristics of flexibility and firmness,and a unit area load capacity of MXene/WPU was 1.9 mg/cm^(2),the conductivity 760 S/m,and the electromagnetic shielding effectiveness up to 42 dB(8.2-12.4 GHz);and this convenient and effective method can be used to prepare lightweight and flexible electromagnetic shielding materials,promising broad application prospects in the field of wearable products.
基金supported by China Huaneng Group Key R&D Program(HNKJ22-H104)the Science and Technology Programs of Fujian Province(2022H0005)+1 种基金the Fundamental Research Funds for the Central Universities(20720240067)Technology Projects of Innovation Laboratory for Sciences and Technologies of Energy Materials of Fujian Province(RD2020020101 and RD2022040601).
文摘Currently,perovskite solar cells have achieved commendable progresses in power conversion efficiency(PCE)and operational stability.However,some conventional laboratory-scale fabrication methods become challenging when scaling up material syntheses or device production.Particularly,the prolonged high-temperature annealing process for the crystallization of perovskites requires a substantial amount of energy consumption and impact the modules’throughput.Here,we report a modified near-infrared annealing(NIRA)process,which involves the excess PbI_(2)engineered crystallization,efficiently reduces the preparation time for perovskite active layer to within 20 s compared to dozens of min in conventional hot plate annealing(HPA)process.The study showed that the incorporated PbI_(2)promoted the consistent nucleation of the perovskite film,leading to the subsequent rapid and homogeneous crystallization at the NIRA stage.Thus,highly crystalized perovskite film was realized with even better crystallization performance than conventional HPA-based film.Ultimately,efficient perovskite solar modules of 36 and 100 cm^(2)were readily fabricated with the optimal PCEs of 22.03%and 20.18%,respectively.This study demonstrates,for the first time,the successful achievement of homogeneous and high-quality crystallization in large-area perovskite films through rapid NIRA processing.This approach not only significantly reduces energy consumption during production,but also substantially shortens the manufacturing cycle,paving a new path toward the commercial-scale application of perovskite solar modules.
基金supported by the National Natural Science Foundation of China(22179050,21875089,51973080)。
文摘The extreme instability of pureα-phase FAPbI_(3) under high humidity conditions restricts the highthroughput fabrication in unmodified air environments,resulting in poor performance ofα-phase FAPbI_(3) perovskite devices obtained by scalable fabrication methods.Here we synthesized hyperbranched copper phthalocyanine(HCuPc)as a supramolecular additive with twisted phthalocyanine units to realize the molecular-level encapsulation at the grain boundaries through supramolecular interaction,which greatly broadened the processing window of FAPbI_(3) under high humidity.At the same time,unlike traditional encapsulation layer that carrier can only be collected by tunneling effect,the twisted phthalocyanine ring of HCu Pc in perovskite films is more conducive to hole extraction.Finally,a record efficiency was achieved in pure FAPbI_(3) based inverted structured solar cell by blade-coating to the best of our knowledge,even under unmodified humid air conditions(relative humidity of 65%–85%).The best operational stability of 3D pure FAPbI_(3) devices can also be achieved at the same time and unencapsulated HCuPc-FAPbI_(3) device can even operate with negligible degradation for 100 h in the open air(RH 30%–40%).
基金HS acknowledges the financial support from the National Natural Science Foundation of China(Grant No.62374065)the Interdisciplinary Research promotion of HUST(No.2023JCYJ040)+4 种基金the Innovation Project of Optics Valley Laboratory(No.OVL2021BG008)the Program of Science Technology of Wenzhou City(No.G20210011)HH acknowledges the fnancial support from the Innovation and Technology Commission(No.MHP/104/21)the Shenzhen Science Technology and Innovation Commission(No.JCYJ20210324125612035)the City University of Hong Kong(Nos.9360140,7005720,9667229,9680331,7005580,and 9678291)。
文摘Infrared solar cells are more efective than normal bandgap solar cells at reducing the spectral loss in the near-infrared region,thus also at broadening the absorption spectra and improving power conversion efciency.PbS colloidal quantum dots(QDs)with tunable bandgap are ideal infrared photovoltaic materials.However,QD solar cell production sufers from small-areabased spin-coating fabrication methods and unstable QD ink.Herein,the QD ink stability mechanism was fully investigated according to Lewis acid–base theory and colloid stability theory.We further studied a mixed solvent system using dimethylformamide and butylamine,compatible with the scalable manufacture of method-blade coating.Based on the ink system,100 cm2 of uniform and dense near-infrared PbS QDs(~0.96 eV)flm was successfully prepared by blade coating.The average efciencies of above absorber-based devices reached 11.14%under AM1.5G illumination,and the 800 nm-fltered efciency achieved 4.28%.Both were the top values among blade coating method based devices.The newly developed ink showed excellent stability,and the device performance based on the ink stored for 7 h was similar to that of fresh ink.The matched solvent system for stable PbS QD ink represents a crucial step toward large area blade coating photoelectric devices.
基金supported by the National Natural Science Foundation of China(Grant Nos.11272016&11290152)the Beijing Municipal Commission of Educationthe Ri-Xin Talents Project of Beijing University of Technology
文摘A rotating cantilever sandwich-plate model with a pre-twisted and pre-set angle has been developed to investigate the vibrational behavior of an aero-engine turbine blade with thermal barrier coating(TBC) layers. The classic von Karman plate theory and the first-order shear deformation theory are applied to derive the energy equations of the rotating TBC blade, in which the geometric shapes, the work ambient temperature, and the TBC material properties are considered. The Chebyshev-Ritz method is used to obtain the nature frequency of the rotating TBC blade. For static frequency and modal analysis, the finite-element method(FEM)is also applied to compare and validate the results from the Chebyshev-Ritz method. A good agreement is found among these kinds of methods. For dynamic frequency, the results are analyzed in detail concerning the influence of system parameters such as the thickness of the TBC layer, the working temperature, and the pre-twisted and pre-set angle. Finally, the Campbell diagram is demonstrated to analyze the resonance property of the cantilever sandwich TBC blade model.
基金funded by the National Natural Science Foundation of China(Funding No.51206109)
文摘A hot wind tunnel of annular cascade test rig is established for measuring temperature distribution on a real gas turbine blade surface with infrared camera.Besides,conjugate heat transfer numerical simulation is performed to obtain cooling efficiency distribution on both blade substrate surface and coating surface for comparison.The effect of thermal barrier coating on the overall cooling performance for blades is compared under varied mass flow rate of coolant,and spatial difference is also discussed.Results indicate that the cooling efficiency in the leading edge and trailing edge areas of the blade is the lowest.The cooling performance is not only influenced by the internal cooling structures layout inside the blade but also by the flow condition of the mainstream in the external cascade path.Thermal barrier effects of the coating vary at different regions of the blade surface,where higher internal cooling performance exists,more effective the thermal barrier will be,which means the thermal protection effect of coatings is remarkable in these regions.At the designed mass flow ratio condition,the cooling efficiency on the pressure side varies by 0.13 for the coating surface and substrate surface,while this value is 0.09 on the suction side.
基金supported by Shimadzu Scientific Instruments(Columbia,MD,USA)and Canada’s National Science and Engineering Research Council-Industrial Research Chair(NSERC-IRC)program,grant number IRCPJ 184412-15
文摘The solid-phase microextraction technique quantifies analytes without considerably affecting the sample composition.Herein,a proof-of-concept study was conducted to demonstrate the use of coated probe electrospray ionization(coated-PESI)and coated blade spray(CBS)as ambient mass spectrometry approaches for monitoring drug biotransformation.The ability of these methods was investigated for monitoring the dephosphorylation of a prodrug,combretastatin A4 phosphate(CA4P),into its active form,combretastatin A4(CA4),in a cell culture medium supplemented with fetal bovine serum.The CBS spot analysis was modified to achieve the same extraction efficiency as protein precipitation and obtained results in 7 min.Because coated-PESI performs extraction without consuming any samples,it is the preferred technique in the case of a limited sample volume.Although coated-PESI only extracts small quantities of analytes,it uses the desorption solvent volume of 5-10 pL,resulting in high sensitivity,thus allowing the detection of compounds after only 1 min of extraction.The biotransformation of CA4P into CA4 via phosphatases occurs within the simple matrix,and the proposed sample preparation techniques are suitable for monitoring the biotransformation.
基金the National Science Centre,Poland(Grant No.:2020/04/X/NZ9/01281).
文摘The direct coupling of solid-phase microextraction(SPME)to mass spectrometry(MS)(SPME-MS)has proven to be an effective method for the fast screening and quantitative analysis of compounds in complex matrices such as blood and plasma.In recent years,our lab has developed three novel SPME-MS techniques:SPME-microfluidic open interface-MS(SPME-MOI-MS),coated blade spray-MS(CBS-MS),and SPME-probe electrospray ionization-MS(SPME-PESI-MS).The fast and high-throughput nature of these SPME-MS technologies makes them attractive options for point-of-care analysis and anti-doping testing.However,all these three techniques utilize different SPME geometries and were tested with different MS instruments.Lack of comparative data makes it difficult to determine which of these methodologies is the best option for any given application.This work fills this gap by making a comprehensive comparison of these three technologies with different SPME devices including SPME fibers,CBS blades,and SPME-PESI probes and SPME-liquid chromatography-MS(SPME-LC-MS)for the analysis of drugs of abuse using the same MS instrument.Furthermore,for the first time,we developed different desorption chambers for MOI-MS for coupling with SPME fibers,CBS blades,and SPME-PESI probes,thus illustrating the universality of this approach.In total,eight analytical methods were developed,with the experimental data showing that all the SPME-based methods provided good analytical performance with R^(2)of linearities larger than 0.9925,accuracies between 81%and 118%,and good precision with an RSD%≤13%.
基金We acknow ledge Petroleo Brasileiro S.A.(PETROBRAS)under the project“Research and Development of Perovskite form ulations for production of printed photovoltaic cells and modulesM for funding.S.C.-H and T.M.B.acknowledge to have received funding from Departamen to del Huila’s Scholarship Program No.677 from Huila,Colombia,the European Unions H orizon 2020 research and innovation program under grant agreement no.763989 APOLO,Lazio Region“Gruppi di Ricerca”under project no.85-2017-15373(SIROH)according to L.R.Lazio 13/08,and the Italian Ministry o f University and Research(MIUR)through the PRIN2017 BOOSTER(project n.2017YXX8AZ)grant.This publication reflects only the authors' views and the funding agencies are not liable for any use that may be made of the inform ation contained therein.We thank to Gabriela Amorim for solar cell encapsulation.We thank engineering departm ent at CSEM Brasil for developing the nitrogen blower system.We thank to Centro de Microscopia,Laboratorio de Caracterizacao e de Processam ento de Nanom ateriais from Federal University of M inas Gerais,for providing the experimental facilities and Prof.Wagner da Nova Mussel for XRD results.
文摘Fully printed perovskite solar cells(PSCs)were fabricated in air with all constituent layers,except for electrodes,deposited by the blade coating technique.The PSCs incorporated,for the first time,a nanometer-thick printed bathocuproine(BCP)hole blocking buffer using blade coating and deposited at relative humidity up to 50%.The PSCs with a p-i-n structure(glass/indium tin oxide(ITO)/poly(3,4-ethylenedioxythiophene)polystyrene sulfonate(PEDOT:PSS)/CH_(3)NH_(3)Pbl_(3)/[6,6]-phenyl-C_(61)-butyric acid methyl ester(PCBM)/BCP/Ag)delivered a maximum power conversion efficiency(PCE)of 14.9%on an active area of 0.5 cm^(2)when measured under standard test conditions.The PSCs with a blade coated BCP delivered performance of 10%and 63%higher(in relative terms)than those incorporating a spin coated BCP or without any BCP film,respectively.The atomic force microscopy(AFM)showed that blade coated films were more homogeneous and acted also as a surface planarizer leading to a reduction of roughness which improved BCP/Ag interface lowering charge recombination.The demonstration of 15%efficient devices with all constituent layers,including nanometer-thick BCP(〜10 nm),deposited by blade coating in air,demonstrates a route for industrialization of this technology.
基金supported by the National Key Research and Development Program of China(Grant No.2022YFB4200302)the National Natural Science Foundation of China(Grant Nos.52325307,52273188,22075194)+1 种基金Department of Science and Technology of Jiangsu Province(No.BE2022023)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD),Collaborative Innovation Center of Suzhou Nano Science and Technology,and the Key Laboratory of Polymeric Materials Design and Synthesis for Biomedical Function,Soochow University.
文摘Achieving high-performance perovskite solar modules(pero-SMs)over large areas under ambient conditions remains a significant barrier to the commercialization of perovskite photovoltaics.This challenge arises from the strong solvent-perovskite coordination interactions in the hygroscopic perovskite precursor ink,which complicate the control of nucleation-growth kinetics and phase evolution during film formation in the presence of moisture,thereby hindering the formation of high-quality perovskite films.In this work,a“vip-solvent”additive strategy was developed by incorporating N,N-dimethylthioformamide(DMT)into the perovskite precursor ink to effectively modulate the coordination between the solvent and perovskite.It is demonstrated that DMT,structurally similar to the“main-solvent”system(DMF and DMSO),possesses lower coordination ability with Pb2+and forms non-covalent interactions with the primary solvents.These interactions weaken the solvent-perovskite coordination without sacrificing solubility,thereby stabilizing homogeneous nucleation and promoting direct crystallization from the sol-gel phase toα-FAPbI3.As a result,the ambient-printed FAPbI3 films exhibited high quality,with more compact grain stacking,smoother morphology,higher phase purity,and fewer defects.Consequently,the resulting perovskite solar cells(0.062 cm2)and pero-SMs(15.64 cm2)fabricated via blade coating under ambient conditions achieved remarkable power conversion efficiencies(PCEs)of 24.46%and 22.54%,respectively.
基金supported by the National Natural Science Foundation of China (52102332, 52361145847, 52072402, 52203368, 52172260, 52227803, 52222212)the Beijing Natural Science Foundation (2222082)+1 种基金the Ministry of Science and Technology of the People’s Republic of China (2021YFB3800103)the CAS-CSIRO Joint Project (112111KYSB20210017)。
文摘Large pinhole-free,high-crystal-quality per-ovskite films are the key to realizing efficient,stable CsPbI_(3)perovskite modules.In this work,we use the crystal growth modulation strategy to prepare high-quality CsPbI_(3)films from small to large sizes using a new precursor solution with CsI/DMAPbI_(3)/PbI_(2)in a DMAAc/DMF mixed solvent(DMAAc:dimethylamine acetate).The champion small-size CsPbI_(3)de-vice presents a photoelectric conversion efficiency(PCE)above 21%and a certified PCE of 20.05%,and the best blade-coated CsPbI_(3)minimodule exhibits a PCE of 18.3%for an aperture area of 12.39 cm2 and a PCE of 19.9%for an active area of 11.40 cm^(2).In addition,the composition engineering of the precursor solution toward CsPbI_(3)crystallization is explored:the DMAAc/DMF mixed solvent can facilitate phase trans-formation and reduce the nucleation rate,and the mixture of PbI2 and DMAPbI3 will further improve the film micro-structure and uniformity.Consequently,the anti-humidity stability and phase stability of the CsPbI_(3)films are greatly improved,and the corresponding devices exhibit good op-erational stability.CsPbI_(3)modules with simple encapsulation also present excellent long-term storage stability over 150 days.This crystal growth regulation strategy provides a new method to produce large-scale CsPbI_(3)and even hybrid per-ovskite solar cells for future commercialization.
