基于微纳立体结构的蛋白凝胶柔性传感器

       柔性传感是柔性电子的重要研究领域之一，具有可拉伸可弯曲、柔软轻薄的优点，因此广泛应用于生理信号监测、医疗器械以及可穿戴设备上。目前大多数柔性传感器的材料缺乏生物兼容性和可降解性，且其用于提升性能的常见微结构如金字塔微锥、微槽以及微半球等，通常使用光刻、化学刻蚀等传统工艺，流程复杂、费时费力、成本高昂。为了简单高效地制备具有微纳立体结构的灵敏柔性传感器，本文提出了以廉价易得、可降解、具有生物兼容性的蛋白凝胶为材料，基于气泡辅助生成的微纳立体结构，快速大面积制备仿生柔性传感器的方案。

       作为信号采集端，柔性传感器始终沿着更低的成本、更好的性能、更高效的工艺等方向发展，本工作从传感器制备的三个要素包括材料、结构、工艺出发，在柔性传感器材料的选择中优先考虑使用廉价易得、来源广泛、有良好群众基础的蛋清材料，通过气泡辅助生成微结构提高柔性传感器性能，采用受生物微结构产生方式启发的无模板微结构制备工艺，可便捷高效制备用于生理健康监测的柔性传感器。

       本文基于气泡辅助在蛋白凝胶中制备微纳立体结构，在无模板的情况下可控地制备出规则的气泡阵列，具有天然微纳立体气泡结构的蛋白凝胶可用作电容型触觉传感器的介电层，实现柔性传感器的功能，传感响应良好且可降解，工艺简单，成本低，这种材料、结构和工艺未来还能扩展出更多的应用，对柔性传感器的研发和推广具有普遍意义。

     Flexible sensors are one of the important research fields of flexible electronics. It has the advantages of being stretchable, bendable, soft and thin, so it is widely used in physiological signal monitoring, medical devices and wearable devices. At present, most flexible materials lack biocompatibility and degradability. Common microstructures used to improve the performance of flexible sensors usually require traditional processes like photolithography and chemical etching, the process is complex, time-consuming, labor-intensive as well as expensive. In order to simply and efficiently fabricate sensitive and flexible sensors with micro-nano structures, this thesis proposes a micro-nano three-dimensional structure based on bubble-assisted using biocompatible, degradable, cheap and easily available protein gel material.

     As a signal acquisition, flexible sensors have always been developed in the direction of lower cost, better performance, and more efficient processes. This work starts from the three elements of sensor including material, structure, and process. In the selection of flexible sensor materials, priority should be given to the use of egg white materials that are cheap, widely available. To improve the performance of flexible sensors, microstructures are generated with assistant of bubble, and we apply template-free microstructures inspired by biological microstructure generation methods. The technology can conveniently and efficiently prepare flexible sensors for physiological health monitoring.

     In this thesis, regular bubble arrays can be controllably fabricated without templates, and protein gels with micro-nano three-dimensional bubble structures are used to improve the functions of flexible sensors and complete physiological signal monitoring. The egg white gel flexible sensor based on the bubble structure has the advantages of natural micro-nano three-dimensional structure, good sensing response, degradable, simple process and low cost. Material, structure and process mentioned in this thesis can be extended to more applications in the future, which is of general significance for the development and promotion of flexible sensors.

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