A Novel Triboelectric Nanogenerator Based on PVA/CaCl ₂ /GO Nanocomposite Ionic Hydrogel for Monitoring Body Movements and Human‐Machine Interaction

Triboelectric nanogenerators are expected to be an essential feature of smart electronic devices. They can detect various physical stimuli without requiring an external power source and are known for their flexibility, low‐cost, and reliable performance. Due to their potential for monitoring human movements and harvesting energy, they have garnered significant interest. However, developing a triboelectric nanogenerator with high stretchability, flexibility, and output remains challenging. This article introduces a nanocomposite ionic hydrogel triboelectric nanogenerator (NIH‐TN) for monitoring human movements and human machine interface (HMI). This flexible nanogenerator uses an ionic hydrogel as an electrode, made up of polyvinyl alcohol (PVA), calcium chloride, and graphene oxide (GO), to improve its electrical and mechanical properties. The introduced structure overcomes the evaporation of liquid and the reduction of performance associated with electrodes based on conductive hydrogels. After investigation of the affecting parameters and using their optimal levels, the NIH‐TN performs well and remains stable, with an open‐circuit voltage of 180 V, a short circuit current of 15 µA, and a maximum output power of 2.1 W m −2 . It can monitor body movements by placing on the finger, wrist, elbow, and knee joints while it can harvest mechanical energy for powering electronic devices. Additionally, the NIH‐TN can be used to create a flexible tactile keyboard.