Dynamically functioning and highly stretchable epidermal supercapacitor based on vertically aligned gold nanowire skins

Abstract An ideal epidermal supercapacitor should be ultrathin, highly stretchable, and skin‐attachable yet able to function under dynamic deformation states. Past several years have witnessed encouraging progress in stretchable supercapacitors but it remains challenging to achieve an epidermal supercapacitor that can meet all the aforementioned criteria. Here, we report an entire solution‐based strategy to fabricate such kind of epidermal supercapacitor based on enokitake‐like vertically aligned gold nanowires (v‐AuNWs) in conjunction with pseudocapacitive polyaniline and pre‐strain technology. Despite of ultrathin thickness of only around 50 μm, our epidermal supercapacitor exhibited an areal capacitance of 2.3 mF/cm2 with negligible performance deterioration under both static and dynamic stretching of 100% strain. Such performance could also be well‐maintained for the on‐skin applications where wrist being constantly under various motions. Our finding indicates the potential application of the solution‐grown v‐AuNWs in future wearable electronics.