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

doi:10.13801/j.cnki.fhclxb.20230117.006

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

doi: 10.13801/j.cnki.fhclxb.20230117.006

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；TB333
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- 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: 2023-01-18
- 刊出日期: 2023-10-15

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: 静电纺丝法制备有机压电传感器较传统压力传感器具有更好的柔韧性、轻质且透气，在可穿戴传感器研究领域中备受关注。本文提出了一种以静电纺丝工艺制备氯化铋/聚偏氟乙烯-三氟乙烯(BiCl₃/P(VDF-TrFE))复合膜的方法，并以该复合膜为功能层，设计并制备了柔性压电传感器。一定含量BiCl₃加入后，扫描电子显微镜分析结果表明纤维平均直径从619 nm增至1158 nm，且表面更趋光滑，XRD结果证实复合膜的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16.8 V、164 nA，相比纯P(VDF-TrFE)压电薄膜有明显提升，是其2.15倍和2.24倍。压力感知实验显示，在1.28 N的按压力以下，具有较好的线性输出特性，并展现了良好的稳定性和重现性。利用该薄膜设计了柔性可穿戴力感知键盘，该键盘能采集用户的按压力度和持续时间，为柔性键盘等智能织物等相关应用提供了参考。
- 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/poly(vinylidene fluoride-trifluoroethylene) (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 is added, the scanning electron microscope analysis shows that the average diameter of the fiber increases from 619 nm to 1158 nm, and the surface becomes smoother. The X-ray diffraction pattern confirms that β phase content of the composite film has been significantly improved. The piezoelectric response testing results show that the open circuit peak-to-peak voltage (V_oc) and short-circuit current (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 2.15 and 2.24 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 could 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 1 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 1. 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

P(VDF-TrFE)—Poly(vinylidene fluoride-trifluoroethylene)

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图 2 静电纺丝系统示意图

Figure 2. Schematic diagram for the electrospinning system

RH—Relative humidity

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图 3 不同浓度的 BiCl₃/P(VDF-TrFE)复合膜的SEM图像：(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%BiCl₃单根纤维；(g) 2wt%BiCl₃单根纤维

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

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图 4 (a) 不同浓度的复合膜 XRD图谱；(b) P(VDF-TrFE)与BiCl₃相互作用机制

Figure 4. (a) XRD patterns 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

TIA—Transresistance amplifier

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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；2wt%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 current (d) at 2wt%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 sensing keyboard; (b) MSP430 F5529 Launchpad and 6-channel charge amplification circuit; (c) Keyboard operation demonstration; (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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