Inflammation-free and gas-permeable on-skin triboelectric nanogenerator using soluble nanofibers

In recent years, wearable triboelectric nanogenerators (TENGs) and related on-skin nano-systems are drawing massive attentions due to their potential applications in sensory devices, electronics skins and portable energy packages. However, most of these TENG devices still employ adhesive tape to attach on human skin, which may cause many side effects, such as inflammation, allergy and discomfort symptoms in the long term. Therefore, it is quite necessary to find a simple and skin-friendly bonding method to directly stick TENG to human skin. Here, we fabricated a blended nanofiber membranes (NM) which is obtained by the mixed electro-spinning technique using polyvinyl alcohol and polyvinylidene fluoride nanofibers. This blended NM can directly attach on skin with the help of a tiny amount of water and no uncomfortable symptoms or allergy can be found during a long period of operation. The TENG device based on this NM can not only achieve good output performance, but also realize a wearable energy generator with inflammation-free and highly gas-permeable characteristics. The blended NM have excellent air permeability (Gurley value = 1.4 s/300 ml-3.3 s/300 ml). The demonstrated concept of this skin-friendly bonding method and NM-based TENG have promising applications in the field of wearable/potable sensory devices, electronics skins, artificial muscles, flexible robots and so on.