The emerging interfacial polarization strategy exhibits applicative potential in piezoelectric enhancement.However,there is an ongoing effort to address the inherent limitations arising from charge bridging phenomena ...The emerging interfacial polarization strategy exhibits applicative potential in piezoelectric enhancement.However,there is an ongoing effort to address the inherent limitations arising from charge bridging phenomena and stochastic interface disorder that plague the improvement of piezoelectric performance.Here,we report a dual structure reinforced MXene/PVDF-TrFE piezoelectric composite,whose piezoelectricity is enhanced under the coupling effect of interfacial polarization and structural design.Synergistically,molecular dynamics simulations,density functional theory calculations and experimental validation revealed the details of interfacial interactions,which promotes the net spontaneous polarization of PVDF-TrFE from the 0.56 to 31.41 Debye.The oriented MXene distribution and porous structure not only tripled the piezoelectric response but also achieved an eightfold increase in sensitivity within the low-pressure region,along with demonstrating cyclic stability exceeding 20,000 cycles.The properties reinforcement originating from dual structure is elucidated through the finite element simulation and experimental validation.Attributed to the excellent piezoelectric response and deep learning algorithm,the sensor can effectively recognize the signals of artery pulse and finger flexion.Finally,a 3×3 sensor array is fabricated to monitor the pressure distribution wirelessly.This study provides an innovative methodology for reinforcing interfacial polarized piezoelectric materials and insight into structural designs.展开更多
The effects of calcined lead--zirconate-titanate(PZT)powders on the electric properties of PZT/polyvinylidene-tifluorethylene copolymer(PVDF-TrFE)composites thick films were studied in this paper.Firstly,the PZT powde...The effects of calcined lead--zirconate-titanate(PZT)powders on the electric properties of PZT/polyvinylidene-tifluorethylene copolymer(PVDF-TrFE)composites thick films were studied in this paper.Firstly,the PZT powders synthesized by hydrothermal method were calcined at different temperatures ranging from 300℃ to 900℃,and then the PZT/PVDF-TrFE composites films were produced by casting PZT/PVDF-TrFE suspension onto the indium-tin-oxide(ITO)-coated glass substrates.Electric properties,including dielectric and pyroelectric performances of thick films consisting of PZT powders calcined at different temperatures were tested.The highest pyroelectric cofficient obtained in the sample using 700℃ calcined PZT powders was 96μCm^(-2)K^(-1),which was 20%higher than the composites made of uncalcined powders.Additionally,the highest detectivity figure-of merit(FOM)(FD)of the composite was 1.36×10^(-5)Pa^(-1/2),which increased about 13.5%compared to the one using uncalcined powders.展开更多
Ferroelectric polymer poly(vinylidene fluoride)(PVDF)shows excellent electro-activity and is promising for flexible electronic devices.However,the processing of PVDF into the favourable ferroelectric structure(β-phas...Ferroelectric polymer poly(vinylidene fluoride)(PVDF)shows excellent electro-activity and is promising for flexible electronic devices.However,the processing of PVDF into the favourable ferroelectric structure(β-phase)presents difficulties,while its copolymer with trifluoroethylene(PVDF-TrFE)can directly crystallize into β-phase,but shows limited thermal stability and high-cost processing.As a result,an easily implementable method,pressing-and-folding(P&F),was used to produce highly compatible blended films of PVDF and PVDF-TrFE without using any hazardous solvent or complex polymer processing equipment.Hot-pressed PVDF(molecular weight:530 kg/mol)and PVDF-TrFE(molar ratio:51/49)films were firstly stacked before undergoing P&F treatment.Compared to extrusion-blended films before and after P&F,the P&F stacked films showed isotropic crystalline structure of b-phase,as confirmed using X-ray diffraction and infrared spectroscopy.The ferroelectric remnant polarization of the P&F stacked films is 0.068 C/m^(2),surpassing pure PVDF-TrFE(0.062 C/m^(2))and the simulated value of remnant polarization of pure PVDF(~0.065 C/m^(2)).The above findings promise to provide inspirations for new processing strategy on PVDF-based functional polymers.展开更多
基金supported by the National Natural Science Foundation of China(No.52303328)the Postdoctoral Innovation Talents Support Program(No.BX20220257)the Sichuan Science and Technology Program(No.2023NSFSC0313).
文摘The emerging interfacial polarization strategy exhibits applicative potential in piezoelectric enhancement.However,there is an ongoing effort to address the inherent limitations arising from charge bridging phenomena and stochastic interface disorder that plague the improvement of piezoelectric performance.Here,we report a dual structure reinforced MXene/PVDF-TrFE piezoelectric composite,whose piezoelectricity is enhanced under the coupling effect of interfacial polarization and structural design.Synergistically,molecular dynamics simulations,density functional theory calculations and experimental validation revealed the details of interfacial interactions,which promotes the net spontaneous polarization of PVDF-TrFE from the 0.56 to 31.41 Debye.The oriented MXene distribution and porous structure not only tripled the piezoelectric response but also achieved an eightfold increase in sensitivity within the low-pressure region,along with demonstrating cyclic stability exceeding 20,000 cycles.The properties reinforcement originating from dual structure is elucidated through the finite element simulation and experimental validation.Attributed to the excellent piezoelectric response and deep learning algorithm,the sensor can effectively recognize the signals of artery pulse and finger flexion.Finally,a 3×3 sensor array is fabricated to monitor the pressure distribution wirelessly.This study provides an innovative methodology for reinforcing interfacial polarized piezoelectric materials and insight into structural designs.
基金supported by the National Natural Science Foundation of China(NSFC.51102037)the Fundamental Research Funds for the Central Universities from UESTC(No.ZYGX2010J030 and No.ZYGX2011J023).
文摘The effects of calcined lead--zirconate-titanate(PZT)powders on the electric properties of PZT/polyvinylidene-tifluorethylene copolymer(PVDF-TrFE)composites thick films were studied in this paper.Firstly,the PZT powders synthesized by hydrothermal method were calcined at different temperatures ranging from 300℃ to 900℃,and then the PZT/PVDF-TrFE composites films were produced by casting PZT/PVDF-TrFE suspension onto the indium-tin-oxide(ITO)-coated glass substrates.Electric properties,including dielectric and pyroelectric performances of thick films consisting of PZT powders calcined at different temperatures were tested.The highest pyroelectric cofficient obtained in the sample using 700℃ calcined PZT powders was 96μCm^(-2)K^(-1),which was 20%higher than the composites made of uncalcined powders.Additionally,the highest detectivity figure-of merit(FOM)(FD)of the composite was 1.36×10^(-5)Pa^(-1/2),which increased about 13.5%compared to the one using uncalcined powders.
基金This work is sponsored by National Natural Science Foundation of China(52103024)Fundamental Research Funds for the Central Universities(2232021D-01)+2 种基金Shanghai Pujiang Program(20PJ1400600)the fellowship of the China Postdoctoral Science Foundation(2021M690646)Engineering and Physical Sciences Research Council(EPSRC)(EP/L017695/1).
文摘Ferroelectric polymer poly(vinylidene fluoride)(PVDF)shows excellent electro-activity and is promising for flexible electronic devices.However,the processing of PVDF into the favourable ferroelectric structure(β-phase)presents difficulties,while its copolymer with trifluoroethylene(PVDF-TrFE)can directly crystallize into β-phase,but shows limited thermal stability and high-cost processing.As a result,an easily implementable method,pressing-and-folding(P&F),was used to produce highly compatible blended films of PVDF and PVDF-TrFE without using any hazardous solvent or complex polymer processing equipment.Hot-pressed PVDF(molecular weight:530 kg/mol)and PVDF-TrFE(molar ratio:51/49)films were firstly stacked before undergoing P&F treatment.Compared to extrusion-blended films before and after P&F,the P&F stacked films showed isotropic crystalline structure of b-phase,as confirmed using X-ray diffraction and infrared spectroscopy.The ferroelectric remnant polarization of the P&F stacked films is 0.068 C/m^(2),surpassing pure PVDF-TrFE(0.062 C/m^(2))and the simulated value of remnant polarization of pure PVDF(~0.065 C/m^(2)).The above findings promise to provide inspirations for new processing strategy on PVDF-based functional polymers.
