Conformal, graphene-based triboelectric nanogenerator for self-powered wearable electronics

Long-term operation is a key requirement for the widespread use of wearable devices and systems. Typical energy-storage and harvesting approaches relying on rigid materials and device structures hinder conformable integration on soft and wrinkled human skin. Here, we report triboelectric nanogenerators (TENGs) that can form directly on human skin and operate wearable devices without recharging process. TENGs with a single-electrode-based structure were fabricated with atomically thin graphene (<1 nm), polydimethylsiloxane (<1.5 µm) and polyethylene terephthalate (<0.9 µm) as the electrode, electrification layer and substrate, respectively, for low flexural rigidity. The conformal TENGs formed on human skin generated electricity by contact with various clothes or the human body. Their triboelectric performance depended on the effective contact area enabled self-powered touch sensors for an assistive communication system by converting analogous information of human motions to digital signals. Thus, TENGs have potential applications in a wide range of future wearable electronics.