Gravure printing is a promising large-scale fabrication method for flexible organic solar cells(FOSCs)because it is compatible with two-dimension patternable roll-to-roll fabrication.However,the unsuitable rheological...Gravure printing is a promising large-scale fabrication method for flexible organic solar cells(FOSCs)because it is compatible with two-dimension patternable roll-to-roll fabrication.However,the unsuitable rheological property of ZnO nanoinks resulted in unevenness and looseness of the gravure-printed ZnO interfacial layer.Here we propose a strategy to manipulate the macroscopic and microscopic of the gravure-printed ZnO films through using mixed solvent and poly(vinylpyrrolidone)(PVP)additive.The regulation of drying speed effectively manipulates the droplets fusion and leveling process and eliminates the printing ribbing structure in the macroscopic morphology.The additive of PVP effectively regulates the rheological property and improves the microscopic compactness of the films.Following this method,large-area ZnO∶PVP films(28×9 cm^(2))with excellent uniformity,compactness,conductivity,and bending durability were fabricated.The power conversion efficiencies of FOSCs with gravure-printed AgNWs and ZnO∶PVP films reached 14.34%and 17.07%for the 1 cm^(2)PM6:Y6 and PM6∶L8-BO flexible devices.The efficiency of 17.07%is the highest value to date for the 1 cm^(2)FOSCs.The use of mixed solvent and PVP addition also significantly enlarged the printing window of ZnO ink,ensuring high-quality printed thin films with thicknesses varying from 30 to 100 nm.展开更多
The rheological properties of nanocellulose aqueous suspensions play a critical role in the development of nanocellulose-based bulk materials.High-crystalline,high-aspect ratio,and slender nanofibrillated cellulose(NF...The rheological properties of nanocellulose aqueous suspensions play a critical role in the development of nanocellulose-based bulk materials.High-crystalline,high-aspect ratio,and slender nanofibrillated cellulose(NFC)were extracted from four biomass resources.The cellulose nanofibrils and nanofibril bundles formed inter-connected networks in the NFC aqueous suspensions.The storage moduli of the suspensions with different concentrations were higher than their corresponding loss moduli.As the concentration increased,the storage and loss modulus of NFC dispersion increased.When the shear rate increased to a certain value,there were differences in the changing trend of the rheological behavior of NFC aqueous suspensions derived from different biomass resources and the suspensions with different solid concentrations.NFC dispersion’s storage and loss modulus increased when the temperature rose to nearly 80℃.We hope this study can deepen the understanding of the rheological properties of NFC colloids derived from different biomass resources.展开更多
Herein the biowaste by-product spent coffee grounds(SCGs)from coffee industry were incorporated into asphalt binders for performance enhancement.From the analysis of Fourier transform infrared spectroscopy(FTIR),diffe...Herein the biowaste by-product spent coffee grounds(SCGs)from coffee industry were incorporated into asphalt binders for performance enhancement.From the analysis of Fourier transform infrared spectroscopy(FTIR),differential scanning calorimetry(DSC),dynamic shear rheometer(DSR),and Brookfield viscosity rheometer,it is confirmed that SCGs have potential prospects as bio-waste modifiers in the application of sustainable pavements.Results demonstrated that the modification process was mainly based on physical reinforcement.Compared with that of the neat asphalt,the shearing stress-resistant ability and high-temperature performance of the SCGs modified binders with the appropriate addition presented a bit of improvement;whereas the binders with 1%and 3%SCGs exhibited remarkably enhanced low-temperature stability.However,notable weaknesses of practical performance were shown for the binder with excessive content of SCGs,indicating the necessity of proportion selecting before application.展开更多
基金supported by the National Natural Science Foundation of China(22135001)Youth Innovation Promotion Association(2019317)+2 种基金the Young Cross Team Project of CAS(JCTD-2021-14)CAS-CSIRO joint project of Chinese Academy of Sciences(121E32KYSB20190021)Vacuum Interconnected Nanotech Workstation,Suzhou Institute of Nano-Tech and Nano-Bionics of Chinese Academy of Sciences(CAS)
文摘Gravure printing is a promising large-scale fabrication method for flexible organic solar cells(FOSCs)because it is compatible with two-dimension patternable roll-to-roll fabrication.However,the unsuitable rheological property of ZnO nanoinks resulted in unevenness and looseness of the gravure-printed ZnO interfacial layer.Here we propose a strategy to manipulate the macroscopic and microscopic of the gravure-printed ZnO films through using mixed solvent and poly(vinylpyrrolidone)(PVP)additive.The regulation of drying speed effectively manipulates the droplets fusion and leveling process and eliminates the printing ribbing structure in the macroscopic morphology.The additive of PVP effectively regulates the rheological property and improves the microscopic compactness of the films.Following this method,large-area ZnO∶PVP films(28×9 cm^(2))with excellent uniformity,compactness,conductivity,and bending durability were fabricated.The power conversion efficiencies of FOSCs with gravure-printed AgNWs and ZnO∶PVP films reached 14.34%and 17.07%for the 1 cm^(2)PM6:Y6 and PM6∶L8-BO flexible devices.The efficiency of 17.07%is the highest value to date for the 1 cm^(2)FOSCs.The use of mixed solvent and PVP addition also significantly enlarged the printing window of ZnO ink,ensuring high-quality printed thin films with thicknesses varying from 30 to 100 nm.
基金supported in part by the Fundamental Research Funds for the Central Universities(2572019BB03 and 2572021CG01)the Startup Fund and the Catalyst Fund from Rowan University and the Research Grant(PC 20-22)from the New Jersey Health Foundation from USAthe Grant(DMR-2116353)from the National Science Foundation.
文摘The rheological properties of nanocellulose aqueous suspensions play a critical role in the development of nanocellulose-based bulk materials.High-crystalline,high-aspect ratio,and slender nanofibrillated cellulose(NFC)were extracted from four biomass resources.The cellulose nanofibrils and nanofibril bundles formed inter-connected networks in the NFC aqueous suspensions.The storage moduli of the suspensions with different concentrations were higher than their corresponding loss moduli.As the concentration increased,the storage and loss modulus of NFC dispersion increased.When the shear rate increased to a certain value,there were differences in the changing trend of the rheological behavior of NFC aqueous suspensions derived from different biomass resources and the suspensions with different solid concentrations.NFC dispersion’s storage and loss modulus increased when the temperature rose to nearly 80℃.We hope this study can deepen the understanding of the rheological properties of NFC colloids derived from different biomass resources.
文摘Herein the biowaste by-product spent coffee grounds(SCGs)from coffee industry were incorporated into asphalt binders for performance enhancement.From the analysis of Fourier transform infrared spectroscopy(FTIR),differential scanning calorimetry(DSC),dynamic shear rheometer(DSR),and Brookfield viscosity rheometer,it is confirmed that SCGs have potential prospects as bio-waste modifiers in the application of sustainable pavements.Results demonstrated that the modification process was mainly based on physical reinforcement.Compared with that of the neat asphalt,the shearing stress-resistant ability and high-temperature performance of the SCGs modified binders with the appropriate addition presented a bit of improvement;whereas the binders with 1%and 3%SCGs exhibited remarkably enhanced low-temperature stability.However,notable weaknesses of practical performance were shown for the binder with excessive content of SCGs,indicating the necessity of proportion selecting before application.