Ferroelectrics(FEs)have shown great potential in sensors,actuators,and electrocaloric cooling due to their direct cross-couplings between electric polarization and mechanical,thermal,and dielectric properties[1−3]Comp...Ferroelectrics(FEs)have shown great potential in sensors,actuators,and electrocaloric cooling due to their direct cross-couplings between electric polarization and mechanical,thermal,and dielectric properties[1−3]Compared with oxide FEs,polymer FEs possess good flexible and shape adaptability,making them promising candidates for flexible electronics and biocompatible devices[4].展开更多
A cross-linkable fluorinated poly (ether ether ketone) (FPEEK) was synthesized for the fabrication of arrayed waveguide grating (AWG) multiplexer. The results of thermal gravimetric analysis (TGA) and near-infrared ab...A cross-linkable fluorinated poly (ether ether ketone) (FPEEK) was synthesized for the fabrication of arrayed waveguide grating (AWG) multiplexer. The results of thermal gravimetric analysis (TGA) and near-infrared absorption spectrum show that the materials have high thermal stability and high optical transparency in the infrared communication region. The refractive index of FPEEK can be controlled easily by changing the fluorine content of the materials. The 32-channel AWG multiplexer is fabricated using the FPEEK and oxygen reactive ion etching technology. The AWG multiplexer exhibits that the insertion loss is from 12.8 to 17.8 dB and the channel crosstalk is less than-20 dB. The wavelength channel spacing and the center wavelength are 0.8nm and 1548nm, respectively.展开更多
Five fluorine-containing vinyl ether monomers were prepared by the reaction between 2-vinyloxy ethanol, a fluorinated alcohol and hexafluorobenzene in the presence of sodium hydride in dimethylformamide. Two represent...Five fluorine-containing vinyl ether monomers were prepared by the reaction between 2-vinyloxy ethanol, a fluorinated alcohol and hexafluorobenzene in the presence of sodium hydride in dimethylformamide. Two representative properties of these monomers, UV-curing behavior initiated by a cationic photo-initiator PAG 201 and surface free energy of coating films, were investigated. Photo-polymerization proceeded both rapidly and completely with a high double-bond conversion (〉 90%) and a fast curing rate (maximum curing time 〈 21 s) for three monomers. The surface energies of the monomers and the resulting polymer films were then investigated. The minimum surface free energy of the UV-cured homopolymer films reaches 7.1 mJ/m2. X-ray photoelectron spectroscopy data show that the low surthce tension is influenced by fluorine content in the soft segments and fluorinated chains' migration to the surface. The five monomers exhibit low viscosity, low surface energy, good thermal stability and good photo-polymerization properties, which make them great candidates for UV coating and photoresist applications.展开更多
Currently,the practical application of liquid lithium-ion batteries faces challenges in meeting the requirements of high energy density and safety.To address concerns such as electrolyte leakage and flammability,solid...Currently,the practical application of liquid lithium-ion batteries faces challenges in meeting the requirements of high energy density and safety.To address concerns such as electrolyte leakage and flammability,solid polymer electrolytes(SPEs)have emerged as promising alternatives to liquid electrolytes.SPEs,particularly those synthesized via in situ polymerization processes,offer advantages in establishing robust interface contacts and compatibility with existing industrial production lines.However,the electrochemical stability of SPEs remains a hurdle for high-voltage lithium metal batteries(LMBs).To enhance interface uniformity,electrochemical stability,and thermal stability,researchers commonly employ fluorination strategies,thus expanding the potential of SPEs in high-voltage,long-cycling LMBs.Fluorine plays a crucial role in achieving these objectives due to its high electronegativity,polarization,outstanding dielectric properties,strong bond strength,stability,and hydrophobic nature.In this study,we delve into how fluorinated electrolytes improve interface stability between SPEs and electrodes by examining their underlying mechanisms.Besides,we provide an overview of current fluorination strategies and their impact on battery performance.Furthermore,we discuss challenges and issues associated with current in situ polymerized fluorinated SPE routes and propose practical strategies for consideration.展开更多
Gel polymer electrolytes(GPEs)have shown great potential to improve the safety and performance of lithium metal batteries(LMBs),offering benefits such as improved mechanical properties,uniform lithium deposition,suppr...Gel polymer electrolytes(GPEs)have shown great potential to improve the safety and performance of lithium metal batteries(LMBs),offering benefits such as improved mechanical properties,uniform lithium deposition,suppression of dendrite growth,and minimized electrolyte leakage.Nonetheless,several challenges persist,including the solid electrolyte interphase(SEI)instability,suboptimal ionic conductivity,inherent flammability,and an inability to operate at high voltage,significantly hindering their long-term stability and capacity retention.Given fluorine atoms'small atomic radius and high electronegativity,fluorinated gel electrolytes(FGPEs)offer distinct advantages in mitigating these challenges.This review systematically examines the role of fluorine in enhancing the performance of GPEs,with particular emphasis on fluorine's role in improving the SEI composition in GPEs.Additionally,the review elucidates the mechanism of thermal runaway in LMBs and investigates fluorine's contribution to enhancing the flame retardancy of these batteries.The article also details the role of fluorinated components in facilitating lithium-ion transport and evaluates the suitability of fluorinated gel polymer electrolytes for highvoltage applications.Finally,the review elaborates on design strategies for advancing FGPEs and underscores their potential to address critical challenges in lithium metal battery technology.展开更多
Utilizing the periodically structured metal-organic framework (MOF) as the reaction vessel is a promising technique to achieve the aligned polymer molecular chains, where the diffusion procedure of the polymer monom...Utilizing the periodically structured metal-organic framework (MOF) as the reaction vessel is a promising technique to achieve the aligned polymer molecular chains, where the diffusion procedure of the polymer monomer inside MOF is one of the key mechanisms. To investigate the diffusion mechanism of fluorinated polymer monomers in MOFs, in this paper the molecular dynamics simulations combined with the density functional theory and the Monte Carlo method are used and the all-atom models of TFMA (trifluoroethyl methacrylate) monomer and two types of MOFs,[Zn2(BDC)2(TED)]n and[Zn2(BPDC)2(TED)]n, are established. The diffusion behaviors of TFMA monomer in these two MOFs are simulated and the main influencing factors are analyzed. The obtained results are as follows. First, the electrostatic interactions between TFMA monomers and MOFs cause the monomers to concentrate in the MOF channel, which slows down the monomer diffusion. Second, the anisotropic shape of the one-dimensional MOF channel leads to different diffusion speeds of monomers in different directions. Third, MOF with a larger pore diameter due to a longer organic ligand,[Zn2(BPDC)2(TED)]n in this paper, facilitates the diffusion of monomers in the MOF channel. Finally, as the number of monomers increases, the self-diffusion coefficient is reduced by the steric effect.展开更多
Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering ...Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering detector and contact angle meter. Influences of amount of DMDAAC on the properties of resultant latex and its film were investigated in detail. Results show that the particle size of the latex has the minimum value knd the zeta potential of the latex is increased when the amount of DMDAAC is increased. In addition, the particle size of the latex is unimodal distribution when the amount of DMDAAC is not more than 2.5%. However, the particle size of the latex is bimodal distribution when the amount of DMDAAC is more than 2.5%. The contact angle is varied slightly with the increase of amount of DMDAAC when it is not more than 2.5%. Nevertheless, the contact angle is decreased with the increase of the amount of DMDAAC when it is more than 2.5%.展开更多
A series of fluorinated copolyimides containing phthalazinone moieties were prepared from 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride(6FDA),3,3'4,4'-benzophenone-tetracarboxylic dianhydride(BPDA)...A series of fluorinated copolyimides containing phthalazinone moieties were prepared from 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride(6FDA),3,3'4,4'-benzophenone-tetracarboxylic dianhydride(BPDA)and2-(4-aminophenyl)-4-[4-(4-aminophenoxyl)phenyl]-2,3-phthalazin-1-one(DHPZ-2NH_2)for making polymeric opticalwaveguides.The resulting copolymers containing 0-50 mo1% BPDA/DHPZ-2NH_2 show good solubility and are soluble insome organic polar aprotic solvents.The copolyimides also present excellent thermal stability.These polymers possess highglass transition temperature higher than 603 K and high decomposition temperature above 742 K determined by differentialscanning calorimetry and thennogravimetric analysis,respectively,under a nitrogen atmosphere.Their refractive indicescould be controlled by varying the ratio of 6FDA and BPDA in the copolymer from 0.5 to 1.0,and the in-plane refractiveindices(n_(TE))range from 1.6366 to 1.6668 and the out-of-plane refractive indices(n_(TM))from 1.6024 to 1.6280 at 632.8 nm.The polymers birefringence(0.0342-0.0388)is almost independent of the 6FDA content of copolymer,which indicated thatthe phthalazinone-containing copolyimides could be suitable to fabricate optical waveguides possessing a low polarizationdependent loss(PDL).展开更多
基金support from the Natural Science Fund for Colleges and Universities in Jiangsu Province(24KJB430029)the Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications(NY224032,NY225006).
文摘Ferroelectrics(FEs)have shown great potential in sensors,actuators,and electrocaloric cooling due to their direct cross-couplings between electric polarization and mechanical,thermal,and dielectric properties[1−3]Compared with oxide FEs,polymer FEs possess good flexible and shape adaptability,making them promising candidates for flexible electronics and biocompatible devices[4].
文摘A cross-linkable fluorinated poly (ether ether ketone) (FPEEK) was synthesized for the fabrication of arrayed waveguide grating (AWG) multiplexer. The results of thermal gravimetric analysis (TGA) and near-infrared absorption spectrum show that the materials have high thermal stability and high optical transparency in the infrared communication region. The refractive index of FPEEK can be controlled easily by changing the fluorine content of the materials. The 32-channel AWG multiplexer is fabricated using the FPEEK and oxygen reactive ion etching technology. The AWG multiplexer exhibits that the insertion loss is from 12.8 to 17.8 dB and the channel crosstalk is less than-20 dB. The wavelength channel spacing and the center wavelength are 0.8nm and 1548nm, respectively.
基金financially supported by the Beijing Municipal Natural Science Foundation(No.2112020)
文摘Five fluorine-containing vinyl ether monomers were prepared by the reaction between 2-vinyloxy ethanol, a fluorinated alcohol and hexafluorobenzene in the presence of sodium hydride in dimethylformamide. Two representative properties of these monomers, UV-curing behavior initiated by a cationic photo-initiator PAG 201 and surface free energy of coating films, were investigated. Photo-polymerization proceeded both rapidly and completely with a high double-bond conversion (〉 90%) and a fast curing rate (maximum curing time 〈 21 s) for three monomers. The surface energies of the monomers and the resulting polymer films were then investigated. The minimum surface free energy of the UV-cured homopolymer films reaches 7.1 mJ/m2. X-ray photoelectron spectroscopy data show that the low surthce tension is influenced by fluorine content in the soft segments and fluorinated chains' migration to the surface. The five monomers exhibit low viscosity, low surface energy, good thermal stability and good photo-polymerization properties, which make them great candidates for UV coating and photoresist applications.
基金supported by the National Natural Science Foundation of China(22022813)the Zhejiang Provincial Natural Science Foundation of China(LQ24B030002)the China Postdoctoral Science Foundation(2022M722729,2023T160571).
文摘Currently,the practical application of liquid lithium-ion batteries faces challenges in meeting the requirements of high energy density and safety.To address concerns such as electrolyte leakage and flammability,solid polymer electrolytes(SPEs)have emerged as promising alternatives to liquid electrolytes.SPEs,particularly those synthesized via in situ polymerization processes,offer advantages in establishing robust interface contacts and compatibility with existing industrial production lines.However,the electrochemical stability of SPEs remains a hurdle for high-voltage lithium metal batteries(LMBs).To enhance interface uniformity,electrochemical stability,and thermal stability,researchers commonly employ fluorination strategies,thus expanding the potential of SPEs in high-voltage,long-cycling LMBs.Fluorine plays a crucial role in achieving these objectives due to its high electronegativity,polarization,outstanding dielectric properties,strong bond strength,stability,and hydrophobic nature.In this study,we delve into how fluorinated electrolytes improve interface stability between SPEs and electrodes by examining their underlying mechanisms.Besides,we provide an overview of current fluorination strategies and their impact on battery performance.Furthermore,we discuss challenges and issues associated with current in situ polymerized fluorinated SPE routes and propose practical strategies for consideration.
基金supported by the Key Research and Development Program of Shaanxi Province(2024PT-ZCK-82)the Basic Strengthening Program(2022-JCJQ-JJ-0278)the National Natural Science Foundation of China(52105587)。
文摘Gel polymer electrolytes(GPEs)have shown great potential to improve the safety and performance of lithium metal batteries(LMBs),offering benefits such as improved mechanical properties,uniform lithium deposition,suppression of dendrite growth,and minimized electrolyte leakage.Nonetheless,several challenges persist,including the solid electrolyte interphase(SEI)instability,suboptimal ionic conductivity,inherent flammability,and an inability to operate at high voltage,significantly hindering their long-term stability and capacity retention.Given fluorine atoms'small atomic radius and high electronegativity,fluorinated gel electrolytes(FGPEs)offer distinct advantages in mitigating these challenges.This review systematically examines the role of fluorine in enhancing the performance of GPEs,with particular emphasis on fluorine's role in improving the SEI composition in GPEs.Additionally,the review elucidates the mechanism of thermal runaway in LMBs and investigates fluorine's contribution to enhancing the flame retardancy of these batteries.The article also details the role of fluorinated components in facilitating lithium-ion transport and evaluates the suitability of fluorinated gel polymer electrolytes for highvoltage applications.Finally,the review elaborates on design strategies for advancing FGPEs and underscores their potential to address critical challenges in lithium metal battery technology.
基金Project supported by the National Natural Science Foundation of China(Grant No.61575096)
文摘Utilizing the periodically structured metal-organic framework (MOF) as the reaction vessel is a promising technique to achieve the aligned polymer molecular chains, where the diffusion procedure of the polymer monomer inside MOF is one of the key mechanisms. To investigate the diffusion mechanism of fluorinated polymer monomers in MOFs, in this paper the molecular dynamics simulations combined with the density functional theory and the Monte Carlo method are used and the all-atom models of TFMA (trifluoroethyl methacrylate) monomer and two types of MOFs,[Zn2(BDC)2(TED)]n and[Zn2(BPDC)2(TED)]n, are established. The diffusion behaviors of TFMA monomer in these two MOFs are simulated and the main influencing factors are analyzed. The obtained results are as follows. First, the electrostatic interactions between TFMA monomers and MOFs cause the monomers to concentrate in the MOF channel, which slows down the monomer diffusion. Second, the anisotropic shape of the one-dimensional MOF channel leads to different diffusion speeds of monomers in different directions. Third, MOF with a larger pore diameter due to a longer organic ligand,[Zn2(BPDC)2(TED)]n in this paper, facilitates the diffusion of monomers in the MOF channel. Finally, as the number of monomers increases, the self-diffusion coefficient is reduced by the steric effect.
基金supported by the Science and Technology Department of Zhejiang Province under Grant No. 2010C31040the financial support of Zhejiang Provincial Natural Science Foundation of China(No. Y4100152)Zhejiang University of Technology Natural Science Foundation(No.20100202)
文摘Cationic fluorinated acrylate latex was prepared via semi-continuous emulsion copolymerization of cationic monomer and other monomers. The resultant latex and its film were characterized with dynamic light scattering detector and contact angle meter. Influences of amount of DMDAAC on the properties of resultant latex and its film were investigated in detail. Results show that the particle size of the latex has the minimum value knd the zeta potential of the latex is increased when the amount of DMDAAC is increased. In addition, the particle size of the latex is unimodal distribution when the amount of DMDAAC is not more than 2.5%. However, the particle size of the latex is bimodal distribution when the amount of DMDAAC is more than 2.5%. The contact angle is varied slightly with the increase of amount of DMDAAC when it is not more than 2.5%. Nevertheless, the contact angle is decreased with the increase of the amount of DMDAAC when it is more than 2.5%.
基金This work was supported by the National Natural Science Foundation of China(No.50143013).
文摘A series of fluorinated copolyimides containing phthalazinone moieties were prepared from 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride(6FDA),3,3'4,4'-benzophenone-tetracarboxylic dianhydride(BPDA)and2-(4-aminophenyl)-4-[4-(4-aminophenoxyl)phenyl]-2,3-phthalazin-1-one(DHPZ-2NH_2)for making polymeric opticalwaveguides.The resulting copolymers containing 0-50 mo1% BPDA/DHPZ-2NH_2 show good solubility and are soluble insome organic polar aprotic solvents.The copolyimides also present excellent thermal stability.These polymers possess highglass transition temperature higher than 603 K and high decomposition temperature above 742 K determined by differentialscanning calorimetry and thennogravimetric analysis,respectively,under a nitrogen atmosphere.Their refractive indicescould be controlled by varying the ratio of 6FDA and BPDA in the copolymer from 0.5 to 1.0,and the in-plane refractiveindices(n_(TE))range from 1.6366 to 1.6668 and the out-of-plane refractive indices(n_(TM))from 1.6024 to 1.6280 at 632.8 nm.The polymers birefringence(0.0342-0.0388)is almost independent of the 6FDA content of copolymer,which indicated thatthe phthalazinone-containing copolyimides could be suitable to fabricate optical waveguides possessing a low polarizationdependent loss(PDL).