@article{Yu_Zheng_Liu_Xiao_Huangfu_Guo_2021, title={Superflexible and Lead-Free Piezoelectric Nanogenerator as a Highly Sensitive Self-Powered Sensor for Human Motion Monitoring}, volume={13}, url={https://www.nmlett.org/index.php/nml/article/view/883}, DOI={10.1007/s40820-021-00649-9}, abstractNote={<p>For traditional piezoelectric sensors based on poled ceramics, a low curie temperature (<em>T</em><sub>c</sub>) is a fatal flaw due to the depolarization phenomenon. However, in this study, we find the low <em>T</em><sub>c</sub> would be a benefit for flexible piezoelectric sensors because small alterations of force trigger large changes in polarization. BaTi<sub>0.88</sub>Sn<sub>0.12</sub>O<sub>3</sub> (BTS) with high piezoelectric coefficient and low <em>T</em><sub>c</sub> close to human body temperature is taken as an example for materials of this kind. Continuous piezoelectric BTS films were deposited on the flexible glass fiber fabrics (GFF), self-powered sensors based on the ultra-thin, superflexible, and polarization-free BTS-GFF/PVDF composite piezoelectric films are used for human motion sensing. In the low force region (1–9&nbsp;N), the sensors have the outstanding performance with voltage sensitivity of 1.23&nbsp;V&nbsp;N<sup>−1</sup> and current sensitivity of 41.0 nA N<sup>−1</sup>. The BTS-GFF/PVDF sensors can be used to detect the tiny forces of falling water drops, finger joint motion, tiny surface deformation, and fatigue driving with high sensitivity. This work provides a new paradigm for the preparation of superflexible, highly sensitive and wearable self-powered piezoelectric sensors, and this kind of sensors will have a broad application prospect in the fields of medical rehabilitation, human motion monitoring, and intelligent robot.</p> <p>Highlights:</p> <p>1 Continuous piezoelectric BaTi<sub>0.88</sub>Sn<sub>0.12</sub>O<sub>3</sub> (BTS) films were deposited on glass fiber fabrics successfully.<br>2 Superflexible, highly sensitive self-powered piezoelectric sensors were fabricated based on polarization-free BTS.<br>3 Low curie temperature would be a benefit for flexible piezoelectric sensors because small alterations of force will trigger large changes in polarization.<br>4 The superflexible sensors are highly desirable for wearable devices to detect human motion.</p>}, journal={Nano-Micro Letters}, author={Yu, Di and Zheng, Zhipeng and Liu, Jiadong and Xiao, Hongyuan and Huangfu, Geng and Guo, Yiping}, year={2021}, month={Apr.}, pages={117} }