基于静电纺丝选择性沉积PVDF-TrFE的柔性压电传感器阵列

  近年来，柔性压电式压力传感器以其自供电的优势在可穿戴电子设备中引起广泛关注。目前的研究多集中在通过提高材料性能或使用结构的调整以增加压电响应，而较少地考虑大面积、高分辨率的阵列化应用。传统的旋涂刮涂等方法制备的薄膜需要经过拉伸和电极化才具备压电性能，容易造成电击穿和薄膜损坏。同时，在大面积的压电阵列中，需要复杂耗时的光刻过程，阵列的大小也强烈依赖于晶圆和掩模版尺寸。此外，随着分辨率的提高，相邻敏感元容易受到临近压电单元的串扰。

  针对此问题，本文采用分立压电单元设计，利用选择性静电纺丝沉积纳米纤维，通过有限元仿真对纺丝过程中的电场进行模拟验证了其可行性。随后将制备得到的凸形压电单元图案薄膜作为压电功能层，使得所有压电单元相互机械隔离。仿真验证了该分立压电单元设计能有效地减少压电薄膜变形过程中的串扰。

  根据仿真结果以压电材料PVDF-TrFE（聚偏氟乙烯-三氟乙烯）为对象，通过集电器结构设计，探索最佳纺丝工艺以实现具有良好的图案化的纳米纤维薄膜。成功制备了一种无需光刻的压电传感器阵列。该压电敏感层不需要进行额外的极化，有效避免了薄膜破坏损伤。实验测试证明制成的传感器具有宽线性区域（0-40 N）、良好的线性度（2.5 mV/kPa）和耐用性（超过 25，000 次），并且分立的凸形压电单元具有良好的的抗串扰能力。

  利用双轴步进电机移动收集器可以轻松获得大面积、高分辨率的压电传感阵列，制造过程快速且易于大规模生产。对于一个N × M传感器阵列，该传感器只需要利用N + M根导线，分别检测各通道对地的电势差变化就可以得到施力物体的运动信息。考虑到材料的热释电效应，我们针对温度剧烈变化对器件的影响进行了探讨。此外，我们成功地展示了准确的轨迹识别，以确认无串扰传感器阵列的适用性。

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