基于BiCl<sub>3</sub>/P(VDF-TrFE)膜的柔性压力传感器设计及其在力感知键盘中的应用

骆懿; 廖海; 赵治栋; 王金鹏; 吴颖

基于BiCl₃/P(VDF-TrFE)膜的柔性压力传感器设计及其在力感知键盘中的应用

骆懿¹,
廖海¹,
赵治栋^2, ,,
王金鹏³,
吴颖⁴

1.
杭州电子科技大学　电子信息学院, 杭州 310018
2.
杭州电子科技大学　网络空间安全学院, 杭州 310018
3.
杭州电子科技大学　微电子研究院, 杭州 310018
4.
杭州电子科技大学　教务处, 杭州 310018

详细信息

通讯作者:
赵治栋，博士，教授，博士生导师，研究方向为生物医学信号处理和医学人工智能技术等　E-mail: zhaozd@hdu.edu.cn

中图分类号: TP212.3
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- 文章访问数: 118
- HTML全文浏览量: 89
- 被引次数: 0
出版历程
- 收稿日期: 2022-10-27
- 修回日期: 2022-12-19
- 录用日期: 2023-01-09
- 网络出版日期: 2023-02-02

Design of flexible nano pressure sensor based on BiCl₃/P(VDF-TrFE) composite film and application in force sensing flexible keyboard

1.
School of Electronic Information, Hangzhou Dianzi University, Hangzhou 310018, China
2.
School of Cyberspace Security , Hangzhou Dianzi University, Hangzhou 310018, China
3.
Microelectronics Research Institute , Hangzhou Dianzi University, Hangzhou 310018, China
4.
Academic Affairs Office , Hangzhou Dianzi University, Hangzhou 310018, China

摘要

摘要: 在各种制作压力传感器的有机材料中，聚偏氟乙烯(PVDF)具有良好的生物相容性和压电灵敏度。但相比于无机压电材料，PVDF及其共聚物压电系数较低，限制了其作为压力传感器和能量收集器的性能。为了更低成本的制备出压电性更好且柔软度高的复合膜，本文通过静电纺丝法，制备了基于BiCl₃/P(VDF-TrFE)复合膜的柔性纳米压电薄膜传感器。一定含量BiCl₃加入后，扫描电子显微镜分析结果呈现纤维平均直径从619nm增至1158nm，且表面更趋光滑，X射线衍射图证实复合膜的β相含量得到了明显提高。压电响应测试结果显示，BiCl₃含量为2wt%的P(VDF-TrFE)复合膜开路峰峰值电压和短路电流分别为16.8V、164nA，相比纯P(VDF-TrFE)压电薄膜有明显提升，分别提升了115%、180%。压力感知实验显示，压电薄膜在1.28N的按压力以下，具有较好的线性输出特性。作者利用该复合膜设计了一款柔性可穿戴力感知键盘，该键盘有采集按压力度和持续时间的功能，为柔性键盘等智能织物相关应用提供了参考。1P(VDF-TrFE)的特性及应用(a)和BiCl₃改性后的开路电压(b)
- P(VDF-TrFE) /
- 高压静电纺丝 /
- BiCl₃ /
- 力感知键盘 /
- 柔性传感器
Abstract: The organic piezoelectric sensor prepared by electrospinning is better flexibility, light weight and breathability than the traditional pressure sensor, which has attracted much attention in the field of wearable sensor research. In this paper, a method of preparing BiCl₃/P(VDF-TrFE) composite film by electrospinning was proposed, and the flexible piezoelectric sensor was designed and prepared with the composite film as the functional layer. After a certain amount of BiCl₃ was added, the scanning electron microscope analysis showed that the average diameter of the fiber increased from 619 nm to 1158 nm, and the surface became smoother. The X-ray diffraction pattern confirmed the stability of the composite film β phase content has been significantly improved. The piezoelectric response testing results show that the peak to peak V_oc and I_sc of P(VDF-TrFE) composite films with 2wt% BiCl₃ are 16.8 V and 164 nA, Compared with pure P (VDF TrFE) piezoelectric film, it is obviously improved, 215% and 224% times. The pressure sensing testing results show that the piezoelectric film is good linear output characteristics under the pressure of 1.28 N. A flexible wearable force sensing keyboard was designed with this film, which can collect fingers pressing force and duration time. And it provides a reference solution on smart fabrics such as flexible keyboard applications.
- P(VDF-TrFE) /
- Electrospinning /
- BiCl₃ /
- Force sensing keyboard /
- Flexible sensor

HTML全文

图 2 柔性纳米压电薄膜及传感器制备: (a)实验流程示意图 (b)传感器结构示意图 (c)封装后的传感器光学照片

Figure 2. Preparation of flexible nano piezoelectric films and sensors: (a) Schematic diagram of experiment flow (b) Schematic diagram of sensor structure (c) Photographs of the prepared sensor devise

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图 1 静电纺丝系统示意图

Figure 1. Schematic diagram for the electrospinning system

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图 3 不同浓度的 BiCl3/P(VDF-TrFE)复合膜 SEM 电镜结果：(a) 0wt% ;(b)2wt% ;(c) 5wt%;(d)0wt% BiCl3 复合膜的纤维直径统计;(e) 2wt% BiCl3 复合膜的纤维直径统计;(f) 0wt%单根纤维;(g) 2wt% BiCl3 单根纤维.

Figure 3. SEM results of BiCl3/P(VDF-TrFE) composite membranes with different concentrations：(a) 0wt%;(b) 2wt% (c) 5wt% (d) The diameter distribution of 0wt% BiCl3 composite film (e) The diameter distribution of 2wt% BiCl3 composite film (f) Single fiber of 0wt% BiCl3 composite film (g) Single fiber of 2wt% BiCl3 com- posite film.

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图 4 XRD 结果与分析:(a)不同浓度的复合膜 XRD 结果(b) P(VDF-TrFE)的β相形成示意图

Figure 4. XRD results and analysis:(a) XRD results of composite films with different concentrations. (b) Plausible mechanism of interaction between P(VDF-TrFE) and BiCl3.

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图 5 传感器振动与测试平台示意图

Figure 5. Schematic diagram of sensor vibration and test platform.

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图 6 单次振动结果:(a)振动周期电压分析 (b)传感器运动轨迹分解示意图

Figure 6. Single vibration result:(a) Single vibration voltage result, (b). Schematic diagram of sensor motion track.

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图 7 传感器压电响应测试:不同浓度对开路电压(a)与短路电流(b)的影响；2 wt%BiCl₃下不同频率对开路电压(c) 和短路电流(d)的影响

Figure 7. Sensor piezoelectric response test results: Effect of different concentrations on open-circuit voltage (a) and short-circuit current (b); Effect of Different Frequencies on Open Circuit Voltage (c) and Short Circuit Cur-rent (d) at 2 wt% BiCl₃.

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图 8 按压力与电压的线性度实验:(a)传感器按压结构特写 (b)压电特性的线性拟合 (c)压电灵敏度的重现性验证

Figure 8. Experiment according to the linear relationship between pressure and voltage: (a) Close-up of pressing structure of sensor, (b) Linear fitting of piezoelectric characteristics, (c) Reproducibility verification of piezoelectric sensitivity

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图 9 力感知柔性键盘原型样机搭建: (a)柔性可穿戴力感知键盘示意图 (b) MSP430 F5529 Launchpad 及 6 通道电荷放大电路(c)键盘工作示意图 (d)按压力度与时间特征

Figure 9. Prototype construction of force sensing flexible keyboard:(a) Schematic diagram of flexible wearable force sens- ing keyboard, (b). MSP430 F5529 launchpad and 6-channel charge amplification circuit, (c) Keyboard operation demon- stration, (d) Pressing force and time parameters.

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图 10 不同按键的输入风格可视化

Figure 10. Visualization of input styles of different keys.

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