Ultra-stretchable and shape-memorable ability of an output-boosted triboelectric nanogenerator utilizing highly ordered microdome-crowning thermoplastic polyurethane for a finger-motion detection sensor

We have strategically imprinted hexagonally arranged microdome arrays onto the surface of thermoplastic polyurethane (TPU) to enhance both the output performance and reliability of a triboelectric nanogenerator (TENG). In this study, we present a novel approach, referred to as improved phase separation micromolding (IPS-m-molding), which utilizes a polymer solution replica of honeycomb-concave films created through an improved phase separation process. Beyond offering customizable micropattern arrays, this pioneering technique offers simplicity, scalability, substantial time, and effort savings, thereby effectively surpassing the limitations associated with the existing methods. The microconvex-patterned TPU films obtained by using the present method possess superior elastomeric characteristics, endowing the triboelectret with superior stretchability and remarkable resistance to impacts and compression, particularly notable shape-memory capabilities that facilitate post-frictional deformation recovery. Furthermore, the integration of micropattern arrays onto the TPU surface significantly enhances the TENG's performance, leading to an eight-fold enhancement in the output power compared to a normal flat TENG. More remarkably, this presented TENG based on microconvex TPU demonstrates exceptional durability, enduring a strenuous 50 000-cycle endurance test while continually increasing the output voltage. This improvement is attributed to the expanded effective contact surface area and enhanced lateral deformability of the micropatterns. This inherently high-performance electret holds immense potential for integration into transparent, stretchable TENGs designed for wearable motion-detecting sensors.