Hubei Collaborative Innovation Centre for Advanced Organic Chemical Materials, Faculty of Physics and Electronic Science, College of Chemistry & Chemical Engineering, Hubei University , Wuhan, Hubei Province People's Republic of China.
ACS Appl Mater Interfaces. 2015 Mar 4;7(8):4921-7. doi: 10.1021/am5090012. Epub 2015 Feb 18.
A self-powered active strain sensor based on well-aligned (K,Na)NbO3 piezoelectric nanofibers is successfully fabricated through the electrospinning and polymer packaging process. The device exhibits a fast, active response to dynamic strain by generating impulsive voltage signal that is dependent on the amplitude of the dynamic strains and the vibration frequency. When the frequency is fixed at 1 Hz, the peak to peak value of the voltage increases from ∼1 to ∼40 mV, and the strain changes from 1 to 6%. Furthermore, the output voltage is linearly increased by an order of magnitude with the frequency changing from 0.2 to 5 Hz under the same strain amplitude. The influence of frequency on the output voltage can be further enhanced at higher strain amplitude. This phenomenon is attributed to the increased generating rate of piezoelectric charges under higher strain rate of the nanofibers. By counting the pulse separation of the voltage peaks, the vibration frequency is synchronously measured during the sensing process. The accuracy of the sensing results can be improved by calibration according to the frequency-dependent sensing behavior.
一种基于取向良好的(K,Na)NbO3 压电纳米纤维的自供电主动应变传感器，通过静电纺丝和聚合物封装工艺成功制备。该器件通过产生依赖于动态应变幅度和振动频率的脉冲电压信号，对动态应变表现出快速、主动的响应。当频率固定在 1 Hz 时，电压的峰峰值从约 1 mV 增加到约 40 mV，应变从 1%增加到 6%。此外，在相同应变幅度下，当频率从 0.2 Hz 变化到 5 Hz 时，输出电压线性增加一个数量级。在更高的应变幅度下，频率对输出电压的影响可以进一步增强。这种现象归因于在更高的应变率下，纳米纤维中产生的压电电荷的增加速率。通过计算电压峰值的脉冲间隔，可以在传感过程中同步测量振动频率。根据频率相关的传感行为进行校准，可以提高传感结果的准确性。
