Fabricating organic solar cells(OSCs)in open-air and room-temperature environments is essential for cost-effective roll-to-roll printing,but its performance is limited by non-ideal block and surface morphology of acti...Fabricating organic solar cells(OSCs)in open-air and room-temperature environments is essential for cost-effective roll-to-roll printing,but its performance is limited by non-ideal block and surface morphology of active layer.Herein,we demonstrate a record power conversion efficiency(PCE)of 19.72%in open-air and as-cast processed devices by using a lowcost terpolymer donor(PTQ20-5)to optimize the block and surface morphology.Compared with the counterpart PTQ10,PTQ20-5 shows increased hydrophobicity,which can better prevent the intrusion of H2O molecules in the film formation process in open-air environment,giving excellent humidity tolerance of corresponding devices.Moreover,the enhanced dielectric constant results in reduced exciton binding energy and improved charge transport of PTQ20-5,leading to improved charge separation and transfer,and suppressed carrier recombination in the devices.Besides,the PTQ20-5-based film has more appropriate block morphological features of balanced molecular self-assembly and phase separation,which simultaneously promotes the charge carrier transport and inhibits the carrier recombination at the donor/acceptor interface.This work is of great significance for promoting the industrialization of OSCs.展开更多
We demonstrate a general approach for attaining the bottom morphology of block copolymer（BCP） thin films. In our former measurements on PS-b-PMMA films, surface morphology maps of the BCP films revealed distinct ord...We demonstrate a general approach for attaining the bottom morphology of block copolymer（BCP） thin films. In our former measurements on PS-b-PMMA films, surface morphology maps of the BCP films revealed distinct ordering regimes where the cylinders orient predominantly perpendicular or parallel to the interface and an ‘intermediate＇ regime where these morphologies coexist. However, this earlier work did not explore the bottom morphology of BCP thin films. In this study, we investigated the block copolymer morphology near the solid substrate in the cast block copolymer film having a perpendicular cylinder morphology on the surface.展开更多
This work offers a typical understanding of the factors that govern the nanostructures of poly（4-vinyl pyridine）-b-polystyrene-bpoly（4-vinyl pyridine）（P4 VP-b-PS-b-P4 VP） block copolymers（BCs） in dioxane/water...This work offers a typical understanding of the factors that govern the nanostructures of poly（4-vinyl pyridine）-b-polystyrene-bpoly（4-vinyl pyridine）（P4 VP-b-PS-b-P4 VP） block copolymers（BCs） in dioxane/water, in which water is a selective solvent for the P4 VP block. It is achieved through an investigation of the amphiphilic triblock copolymer micelles by variation of three different factors, including water content（above CWC but under the immobile concentration）, temperature（ranging from 20 °C to 80 °C）, and copolymer composition（low and high PS block length）. Transition of bead-like micelles to vesicles is observed with the increase of water content due to the increase of interfacial energy between the copolymer and the solvent. Effect of temperature superposed on that of water content results in various morphologies, such as beads, fibers, rods, capsules, toroids, lamellae, and vesicles. The interfacial tension between the BC and the solvent increases with the increase of water content but decreases with the increase of temperature, indicating that the micellar morphologies are resulted from the competitive interplay between the temperature and the water content and always change in a direction that decreases the interfacial energy. Based on the micellar structures obtained in this work and the effects of temperature superposed on water concentration, a diagram of phase evolution of different micellar morphologies is illustrated here, covering the temperature range from 20 °C to 80 °C and the water content changing from 20 vol% to 35 vol%. For the investigation of BC composition, morphological transition of vesicle-to-fiber, for high PS length, is observed as compared with bead-to-capsule for low PS length, as the temperature changes from 20 °C to 80 °C. Our research complements the protocols to control over the morphologies and the phase diagram describing P4 VP-b-PS-b-P4 VP micellar nanostructures in aqueous solution.展开更多
基金supported by the National Natural Science Foundation of China(No.52103240)the Science and Technology Department of Henan Province(No.242301420056).
文摘Fabricating organic solar cells(OSCs)in open-air and room-temperature environments is essential for cost-effective roll-to-roll printing,but its performance is limited by non-ideal block and surface morphology of active layer.Herein,we demonstrate a record power conversion efficiency(PCE)of 19.72%in open-air and as-cast processed devices by using a lowcost terpolymer donor(PTQ20-5)to optimize the block and surface morphology.Compared with the counterpart PTQ10,PTQ20-5 shows increased hydrophobicity,which can better prevent the intrusion of H2O molecules in the film formation process in open-air environment,giving excellent humidity tolerance of corresponding devices.Moreover,the enhanced dielectric constant results in reduced exciton binding energy and improved charge transport of PTQ20-5,leading to improved charge separation and transfer,and suppressed carrier recombination in the devices.Besides,the PTQ20-5-based film has more appropriate block morphological features of balanced molecular self-assembly and phase separation,which simultaneously promotes the charge carrier transport and inhibits the carrier recombination at the donor/acceptor interface.This work is of great significance for promoting the industrialization of OSCs.
基金financially supported by the National Natural Science Foundation of China(Nos.2127410321104054 and 21204059)the Undergraduate Innovation Project of Soochow University and the Project for Jiangsu Scientific and Technological Innovation team(2013)
文摘We demonstrate a general approach for attaining the bottom morphology of block copolymer（BCP） thin films. In our former measurements on PS-b-PMMA films, surface morphology maps of the BCP films revealed distinct ordering regimes where the cylinders orient predominantly perpendicular or parallel to the interface and an ‘intermediate＇ regime where these morphologies coexist. However, this earlier work did not explore the bottom morphology of BCP thin films. In this study, we investigated the block copolymer morphology near the solid substrate in the cast block copolymer film having a perpendicular cylinder morphology on the surface.
基金financially supported by Key Lab of Renewable Energy Foundation of Chinese Academy of Sciences(No.Y609JK1001)the National Natural Science Foundation of China for Major Program(Nos.51433009 and 51576201)+2 种基金Natural Science Foundation of Guangdong(No.2015A030313716)Natural Science Foundation of Guangdong for Research Team(No.2015A030312007)Guangdong Science and Technology Project(Nos.2013B050800007 and 2013J4500027)
文摘This work offers a typical understanding of the factors that govern the nanostructures of poly（4-vinyl pyridine）-b-polystyrene-bpoly（4-vinyl pyridine）（P4 VP-b-PS-b-P4 VP） block copolymers（BCs） in dioxane/water, in which water is a selective solvent for the P4 VP block. It is achieved through an investigation of the amphiphilic triblock copolymer micelles by variation of three different factors, including water content（above CWC but under the immobile concentration）, temperature（ranging from 20 °C to 80 °C）, and copolymer composition（low and high PS block length）. Transition of bead-like micelles to vesicles is observed with the increase of water content due to the increase of interfacial energy between the copolymer and the solvent. Effect of temperature superposed on that of water content results in various morphologies, such as beads, fibers, rods, capsules, toroids, lamellae, and vesicles. The interfacial tension between the BC and the solvent increases with the increase of water content but decreases with the increase of temperature, indicating that the micellar morphologies are resulted from the competitive interplay between the temperature and the water content and always change in a direction that decreases the interfacial energy. Based on the micellar structures obtained in this work and the effects of temperature superposed on water concentration, a diagram of phase evolution of different micellar morphologies is illustrated here, covering the temperature range from 20 °C to 80 °C and the water content changing from 20 vol% to 35 vol%. For the investigation of BC composition, morphological transition of vesicle-to-fiber, for high PS length, is observed as compared with bead-to-capsule for low PS length, as the temperature changes from 20 °C to 80 °C. Our research complements the protocols to control over the morphologies and the phase diagram describing P4 VP-b-PS-b-P4 VP micellar nanostructures in aqueous solution.
