Self-powered and photothermal electronic skin patches for accelerating wound healing

Wearable triboelectric nanogenerators (TENGs) have been shown promising for accelerating wound healing by locally generating electrical fields to the wound area. It is highly desirable yet challenging to integrate sensing function and combined therapeutical strategies for a multifunctional flexible TENG electronic skin (E-skin) patch. Herein, we report a single-electrode TENG-based E-skin patch for both sensing motion and promoting wound healing by synergistically utilizing electrical stimulation and photothermal heating capability, which is obtained by using conductive and photothermal polypyrrole/Pluronic F127 hydrogels as the electrolytes. The E-skin patches are biocompatible, stretchable, and shape-adaptable, and in the electrolyte, the polypyrrole imparts conductivity and excellent light-to-heat conversion performance, while F127 enables the phase change capability and flexibility. By combining photothermal heating and real-time electrical stimulation, the E-skin patches can effectively promote angiogenesis, collagen deposition, and re-epithelization to accelerate tissues regeneration and wound closure in a shorter period of ∼ 9 days. Furthermore, the patches demonstrate the abilities to sense human activities, which compensates for partial loss of sensation. We believe that this work will benefit the application of TENGs in skin wound healing, and contribute to the development of multifunctional E-skin patches.