Micromachines
·
2021
·Vol. 12
·期 6
·602
·
IF 2.891
Mingran Liu,Yang Liu,Limin Zhou
With the development of human healthcare devices, smart sensors, e-skins, and pressure sensors with outstanding sensitivity, flexibility, durability and biocompatibility have attracted more and more attention. In this paper, to develop a novel flexible pressure sensor with high sensitivity, different poly (vinylidene fluoride-trifluoroethylene) (PVDF-TrFE)-based composite membranes were fabricated, characterized and tested. To improve the β-phase crystallinity and piezoelectricity of the membranes, and for the purpose of comparison, nano ZnO particles with different concentrations (99:1, 9:1 in a weight ratio of PVDF-TrFE to ZnO) were, respectively added into PVDF-TrFE polymer acting as a nucleating agent and dielectric material. To facilitate the formation of β-phase crystal, the membranes were fabricated by electrospinning method. After the electrospinning, an annealing process was conducted to the fabricated membranes to increase the size and content of β-phase crystal. Then, the fabricated PVDF-TrFE membranes, acting as the core sensing layer, were, respectively built into multiple prototype sensors in a sandwich structure. The sensitivity of the prototype sensors was tested by an auto-clicker. The stimulation of the auto-clicker on the prototype sensors generated electrical signals, and the electrical signals were collected by a self-built testing platform powered by LabVIEW. As a result, combining the addition of ZnO nanofillers and the annealing process, a highly sensitive pressure sensor was fabricated. The optimal peak-to-peak voltage response generated from the prototype sensor was 1.788 V which shows a 75% increase compared to that of the pristine PVDF-TrFE sensor. Furthermore, a human pulse waveform was captured by a prototype sensor which exhibits tremendous prospects for application in healthcare devices.Keywords:PVDF-TrFE;PVDF-TrFE/ZnO;β phase crystal;human pulsation sensor
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS
·
2019
·Vol. 19
·期 4
·830
·
IF 3.031
Jing Han,Dong Li,Chunmao Zhao,Xiaoyan Wang,Jie Li,Xinzhe Wu
A thin film of polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) has good flexibility and simple preparation process. More importantly, compared with PVDF, its piezoelectric β-phase can be easily formed without mechanical stretching. However, its piezoelectricity is relatively lower. Therefore, at present, PVDF-TrFE is always compounded with other kinds of piezoelectric materials to solve this problem. The effect of nano-ZnO doping amount on the sensing characteristics of the piezoelectric films was studied. PVDF-TrFE/nano-ZnO films with different nano-ZnO contents were prepared by spin coating process and packaged. The dispersion of nano-ZnO dopants and the crystallinity of β-phase in piezoelectric films with different nano-ZnO contents were observed by scanning electron microscopy and X-ray diffraction, and the piezoelectric strain constants and dielectric constants were measured, respectively. The effect of different nano-ZnO contents on the output performance of the piezoelectric sensor was obtained by a series of impact experiments. The results show that the piezoelectric strain constant and dielectric constant can be increased by doping nano-ZnO in PVDF-TrFE. Moreover, the doping amount of nano-ZnO in PVDF-TrFE is of great significance for improving the piezoelectric properties of PVDF-TrFE/nano-ZnO thin films. Among the prepared piezoelectric films, the output voltage of PVDF-TrFE/nano-ZnO piezoelectric sensor with 7.5% nano-ZnO doping amount is about 5.5 times that of pure PVDF-TrFE. Thus, the optimal range of the doping amount for nano-ZnO is about 4–10%.Keywords:piezoelectric;PVDF-TrFE;nano-ZnO;flexion sensor
研究领域:
材料科学
·
传感器技术
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Zhirui Hu,Jie Li,Xiaotong Wei,Chen Wang,Yang Cao,Zhiqiang Gao,Jing Han,Yingchun Li
Conductive hydrogels have attracted attention because of their wide application in wearable devices. However, it is still a challenge to achieve conductive hydrogels with high sensitivity and wide frequency band response for smart wearable strain sensors. Here, we report a composite hydrogel with piezoresistive and piezoelectric sensing for flexible strain sensors. The composite hydrogel consists of cross-linked chitosan quaternary ammonium salt (CHACC) as the hydrogel matrix, poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT: PSS) as the conductive filler, and poly(vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE) as the piezoelectric filler. A one-pot thermoforming and solution exchange method was used to synthesize the CHACC/PEDOT: PSS/PVDF-TrFE hydrogel. The hydrogel-based strain sensor exhibits very high sensitivity (GF: 19.3), fast response (response time: 63.2 ms), and wide frequency range (response frequency: 5–25 Hz), while maintaining excellent mechanical properties (elongation at break up to 293%). It can be concluded that enhanced strain-sensing properties of the hydrogel are contributed to both greater change in the relative resistance under stress and wider response to dynamic and static stimulus by adding PVDF-TrFE. This has a broad application in monitoring human motion, detecting subtle movements, and identifying object contours and a hydrogel-based array sensor. This work provides an insight into the design of composite hydrogels based on piezoelectric and piezoresistive sensing with applications for wearable sensors.
研究领域:
材料科学
·
生物医学工程
·
传感器技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SENSORS AND ACTUATORS A-PHYSICAL
·
2022
·
IF 4.291
Bin Zhou,Yu Chen,Kun Hu,Shah Fahad,Yu-xuan Zhou,Yi-ming Yuan,Min Wang
Flexible pressure sensor array has attracted much attention in wearable electronics , but still lacks self-power, high resolution, large-area fabrication, and low crosstalk . Herein, we present a self-powered pressure sensor array via patterned piezoelectric polyvinylidene fluoride-trifluoroethylene (PVDF-TrFE) nanofibrous. The PVDF-TrFE nanofibers were collected by patterned metal ground electrodes that isolated each piezoelectric cell. The isolated sensing cells can effectively reduce the crosstalk caused by additional deformation. The potential from individual cell is detected through the row+column electrode configuration to determine the corresponding pressure point and trajectory information. The as-fabricated pressure sensor array showed an excellent linear piezoelectric response (2.5 mV/kPa), a fast response time (5 ms), and good repeatability (25,000 cycles). Furthermore, our piezoelectric devices with constructed PVDF-TrFE layer are feasible in scaling up to a large-area sensor array. Accurate recognitions of the letter "h" trajectory tracking and tactile sensation by our self-powered tactile sensor array show potential applications in electronic skin and artificial intelligence.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2023
·Vol. 11
·期 14
·4614-4622
·
IF 6.4
Xingmin Liu,Jinling Tong,Jijie Wang,Shaowei Lu,Dongxu Yang,Hongmei Li,Chunzhong Liu,Yutong Song
Flexible piezoelectric pressure sensors have a great application prospect in wearable electronic products due to the advantages of low cost, fast response speed and a self-powered system. However, traditional films based on piezoelectric ceramic/polymer materials face problems such as poor dispersion and insufficient polarization, which hinder the piezoelectric performance of pressure sensors. In this work, MXene was introduced to modify the surface of barium titanate (BaTiO3), which was blended with poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) matrix. An electrospinning method was adapted to fabricate BaTiO3/MXene/PVDF-TrFE composite films. This work proposed a new microscopic sensing mechanism. In addition, this MXene-modification strategy could improve the dispersion of BaTiO3 into the PVDF-TrFE matrix, increase the polarization efficiency and enhance the piezoelectric performance of the sensors. The results showed that the composite film with 0.15 wt% MXene could achieve a remarkable output voltage of 7.6 V. In addition, the tensile strength of the composite film with 0.15 wt% MXene (20.8 MPa) was 77.8% higher than that without MXene (11.7 MPa). Meanwhile, the β phase content of the composite film could reach 81.04%, and the crystallinity increased from 39.49% to 50.31%. The fabricated piezoelectric pressure sensor had a wide detection range (0.2–400 kPa) and a short response time (56 ms). Besides, even after undergoing over 5000 compression cycles, it maintained a stable piezoelectric response. This pressure sensor could quickly respond to joint movements and strenuous exercises in humans. Therefore, this pressure sensor showed great advantages and potential in the application of human motion monitoring.
研究领域:
材料科学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2022
·Vol. 33
·期 7
·3965-3981
·
IF 2.779
Ahmed Arsalan,Jia Yunming,Deb Hridam,Arain Muhammad Fahad,Memon Hafeezullah,Pasha Khalid,Huang Yi,Fan Qinguo,Shao Jianzhong
The use of piezoelectric materials has been increased due to the growing demand for wearable devices. Herein, we report the development of new copolymer poly (vinylidene fluoride-co-trifluoroethylene) (PVDF-TrFE)-based reduced graphene oxide (rGO) and multiwalled carbon nanotubes (MCNTs) loaded electrospun (E-Spun) nanofibers. The rGO-MCNTs loaded PVDF-TrFE nanofibrous mat led to the fabrication of ultra-sensitive piezoelectric pressure sensors for potential wearable health monitoring applications. The doped PVDF-TrFE solution of different weight percentages of rGO-MCNTs as fillers was prepared and used to fabricate an e-spun nanofibrous mat. Complete characterization of resultant materials were carried through diverse instruments which reveals the successful integration of rGO-MCNTs (3.2%) as a dopant that improved the β-phase up to 92%. The DSC analysis further exposes the high thermal stability of the PVDF-TrFE nanofibers mat due to the enhanced crystallinity with the addition of nanofillers. The newly developed sensor’s overall output (based on sensitivity) was calculated under a variable applied pressure range of 0.25 ~ 300 cN at 50 HZ. Results show that the pressure sensor response has improved from 16.125 ~ 0.430 kPa −1 , corresponding to a higher sensitivity under static and dynamic forces in the applied pressure range. These results are of a fundamental study and open new prospects for the hybrid nanofibrous mat as alternative electrode material in the piezoelectric pressure sensor.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2019
·Vol. 30
·期 15
·14007-14021
·
IF 2.195
Ahmed Arsalan,Jia Yunming,Huang Yi,Khoso Nazakat Ali,Deb Hridam,Fan Qinguo,Shao Jianzhong
We developed a high-performance electrically conductive and transparent PVDF-TrFE based electrode for piezoelectric pressures sensor using the electrospinning technique. The electrode was produced by depositing the reduced graphene oxide (rGO), multiwall carbon nanotubes (rGO-MCNTs) via spray coating. Various concentration of rGO and MCNTs were used and optimized for improved electrical performance of the resultant electrode. The deposition of poly (3,4-ethylenedioxythiophene) (PEDOT) was successfully achieved by using vapor phase polymerization (VPP). The morphological characteristics of the as-prepared hybrid composite nanofiber mats were analyzed by using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), Fourier transforms infrared spectroscopy (FT-IR), Raman spectroscopy, X-ray diffraction (X-RD), and UV–visible spectroscopy. The electrical performance of the fabricated composite nanofibers was measured by using a four-point probe device. The results showed significant enhancement in electrical conductivity of the hybrid nanocomposite which increased up to 3916 S cm −1 and sensitivity of the developed pressure sensor was achieved 67.4 kPa −1 . This work suggests that the hybrid nanocomposite can be used for the transparent electrodes in a piezoelectric pressure sensor.
研究领域:
材料科学
·
纳米技术
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Wenbin Sun,Huazhen Liu,Zilong Guo,Anqi Li,Chuang Gao,Chunxiang Lu,Wenjing Zhou,Jiantao Zhang,Yuanyuan Liu
Piezoelectric materials can actively provide a bioelectric microenvironment by converting mechanical stimulations into electrical signals. Combining the excellent flexibility of piezoelectric polymers and the outstanding piezoelectric properties of piezoelectric ceramics, piezoelectric composites are attractive in tissue repair due to their high response to micromechanical stimulations. However, issues such as agglomeration, dielectric differences, and poor interfacial contact with polymers have limited the role of ceramics in improving the overall properties of the composites. In this work, functionalized multiwalled carbon nanotubes (F-MWCNTs) are applied to disperse zinc oxide (ZnO) in the PVDF–TrFE matrix to prepare electrospun composite fiber films. Through the assistance of hydrogen bonding, F-MWCNTs act as bridges connecting ZnO nanoparticles with PVDF–TrFE, which improves the content and crystallinity of the β phase. Furthermore, this strategy enhances the local electric field and reduces dielectric differences, resulting in improved polarization and piezoelectric properties. Results show that the composite fiber film with 0.35 wt % F-MWCNTs could obtain an open-circuit voltage of up to 8.2 V, a β phase content of 83.36%, and a crystallinity of 57.63%. Meanwhile, due to the synergistic effect of F-MWCNTs and ZnO, the tensile strength and Young’s modulus are increased from 3.5 and 11.0 to 6.6 and 19.49 MPa, respectively. Additionally, cellular experiments show that composite fiber films have good bioactivity and promote cell proliferation and adhesion, especially with 0.35 wt % F-MWCNTs. In conclusion, the composite fiber film possesses good piezoelectric and mechanical properties and enhances the cellular activity, making it a good tissue engineering scaffold.
研究领域:
材料科学
·
纳米技术
·
生物医学工程
·
组织工程
✓ 已验证
产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2025
·
IF 6.9
Yanbing Zhu,Hao Xiu,Gang Xue,Tianyong Lei,Yu Wang,Zhongfang Li,Shuren Cong,Tingting Wei
The piezoelectric properties are closely related to the properties of photocatalytic membrane in water environment. Here, a self-polarized g-C 3 N 4 /MoO 3 /PVDF-TrFE membrane with high piezoelectricity was synthesized using a facile spin-coating strategy. In the presence of a low-speed water flow, a stabilized photocatalytic hydrogen evolution rate (538.8 µmol g -1 h −1 ) was obtained for the g-C 3 N 4 /MoO 3 /PVDF-TrFE membrane. Experimental results revealed that the g-C 3 N 4 /MoO 3 induced a reorganization of PVDF-TrFE structure and thereby enlarged the polarization electric field to promote the directional migration of charge carriers and exciton dissociation. Additionally, pressure current test demonstrated that under the same pressure conditions, g-C 3 N 4 /MoO 3 /PVDF-TrFE exhibited a higher response than PVDF-TrFE. This work establishes a new method for the polarization electric field and provides a deeper understanding of the hydrogen evolution mechanism.
研究领域:
材料科学
·
催化化学
·
能源研究
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF POWER SOURCES
·
2022
·
IF 9.794
Jiaqi Zheng,Yunming Wang,Guang Liu,Zhaohan Yu,Shuang Sun,Yue Fu,Dan Chen,Weihao Cai,Jingqiang Cui,Guosheng Wang,Huamin Zhou
Flexible, lightweight and self-charging power units offer a promising solution to supply sustainable and clean electric energy for various electronic devices. Herein, a type of self-charging composite separator based on the poly(vinylidenefluoride-co-trifluoroethylene) (PVDF-TrFE) interconnected skeleton and doped BaTiO 3 piezo-nanoparticles is advocated, which can be employed to fabricate flexible self-charging supercapacitors (SCs) assembled with electrodes and applied to efficiently harvest and storage ubiquitous mechanical energy as electrochemical energy. The high-performance separator with interconnected pores not only exhibits enhanced piezoelectric property ( V oc = 190 V, I sc = 58.10 μA), but also possesses superior ionic conductivity of 2.01 × 10 −3 S/cm and mechanical property (breaking tensile stress of 12.14 MPa). Based on the BaTiO 3 /PVDF-TrFE separators, the self-charging supercapacitors can rapidly self-charge from 110 mV to 748 mV in 8.2 s, which also exhibits admirable specific capacitance (36.36 F/g) and superior cycling stability (capacitance retention of 98% after 10,000 cycles). Possessing outstanding electrochemical performance and mechanical property, the innovational separator with superior feasibility and potential application presented here improves a promising versatile electrolyte design strategy for highly-integrated sustainable self-charging power supply.
研究领域:
材料科学
·
电化学
·
能源存储
·
纳米技术
·
机械工程
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Lingfang Xu,Yu Zhang,Chi Gui,Hanshuo Fang,Ruilong Wang,Haibo Xiao,Shiheng Liang,Changping Yang
BiFeO 3 has been extensively studied as an important single-phase multiferroic material at room temperature in the application fields of energy storage, data storage, spintronics, and electro-magnetic sensors. However, the high leakage current caused by the presence of lattice defects such as vacancies constrains the further development of BiFeO 3 . In this paper, we presented a facile method to overcome the high leakage problem via blending BiFeO 3 nanoparticles into the ferroelectric copolymer PVDF-TrFE matrix and introducing a barrier layer beneath the top Pt dot electrode. The leakage current and ferroelectric characteristics of BiFeO 3 _PVDF-TrFE nanocomposite films were discussed comprehensively. Consequently, compared with the composites without the barrier layer, the leakage current density of the BiFeO 3 _PVDF-TrFE composite films reduced two orders of magnitude after coating a pure copolymer layer. Moreover, the remnant ferroelectric polarization reached ~14 μC cm −2 for a moderate weight content (25 wt%) of BiFeO 3 nanoparticle in the blends, with a remarkably smaller coercive electric field than that of pure PVDF-TrFE films. An electrical conduction blocking mechanism was established to elucidate the optimized electric and ferroelectric properties of nanocomposite films.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Current Nanoscience
·
2024
·Vol. 20
·期 4
·543-553
·
IF 1.4
Liu Yurong,Zeng Xiaolong,Zhu Lin,Wang Cong,Geng Kuiwei,Yao Ruohe
Background: The development of high-performance piezoelectric pressure sensors with outstanding sensitivity, good linearity, flexibility, durability, and biocompatibility is of great significance for smart robotics, human healthcare devices, smart sensors, and electronic skin. Thus,
considerable progress has been achieved in enhancing the piezoelectric property of PVDF-TrFEbased composite pressure sensors by adding various ZnO nanostructures in PVDF-TrFE polymer acting as a nucleating agent and dielectric material. Aims: In this work, flexible pressure sensors with
a sandwich structure based on PVDFTrFE/ nano-ZnO composite sensing film were fabricated using a simple spin-coating method and post-annealing process, while electrospinning and high-voltage polarization processes were not adopted. Methods: Poly (vinylidene fluoride-trifluoroethylene) (PVDF-TrFE)/nano-ZnO
composite films were prepared via spin coating to fabricate flexible piezoelectric pressure sensors. ZnO nanoparticles (ZnO NPs), tetrapod ZnO (T-ZnO) and ZnO nanorods (ZnO NRs) were used as nano-fillers for piezoelectric PVDF-TrFE, to enhance the beta-crystal ratio as well as the crystallinity
of PVDF-TrFE. The structural and surface morphologies of the composite films were investigated using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Results: Among three different types of ZnO nanostructures with a concentration
range (0-7.5 wt%), the sensor with 0.75 wt% ZnO NRs nanofiller exhibits a maximum output voltage of 1.73 V under an external pressure of 3 N and a maximum sensitivity of 586.3 mV/N at the range of 0-3 N. Further, the sensor can generate a clear piezoelectric voltage under bending and twisting
deformation as well as compression and tensile deformation. Conclusion: To summarize, the addition of different concentrations of nano-ZnO can remarkably improve the piezoelectric performance of the composite sensor, and ZnO NRs can achieve better piezoelectric properties of the sensor
as compared to ZnO NPs and T-ZnO. In addition, the sensor with 0.75 wt% ZnO NRs as nanofiller has the highest piezoelectric response, which is about 2.4 times that of the pure PVDF-TrFE sensor. It is demonstrated that the sensor has great potential applications in wearable health monitoring
systems and mechanical stress measurement electronics.
研究领域:
材料科学
·
传感器技术
·
纳米技术
✓ 已验证
DOI
高影响因子