Smart touchless triboelectric nanogenerator towards safeguard and 3D morphological awareness

The advancement of wearable smart electronics in recent years provided vital platforms for robotics, healthcare and human-machine-interfaces. Especially, as a touch-free monitoring sensor, the noncontact working mode endowed the device with superiorities of high sensitivity and favorable longer lifespan. However, the disadvantages of additional power supplies and poor mechanical property of state-of-art noncontact sensors also seriously limited their practical applications. Herein, a novel noncontact triboelectric nanogenerator (NTENG) with self-powering sensing, anti-impact and self-healing properties was developed by integrating graphene/shear-stiffening gel with shear-stiffening elastomer. Based on the electrostatic induction effect, the triboelectric self-powered behavior endowed NTENG with the capability of detecting distance and moving speed of surrounding objects without direct contact. Besides, NTENG demonstrated excellent stretchability of 90% and good self-healing mechanical-electrical properties. Furthermore, NTENG displayed safeguarding performance by efficiently dissipating 41.6% of impact force. Additionally, the NTENG-based arrays could distinguish external targets with various morphologies, and further utilize as smart sensing electric devices in walking stick, elevator button, wearable electronics in noncontact way. Besides, NTENGs could be reshaped into different 3D sensing devices structures. Due to the self-powered noncontact sensing and energy buffering characteristics, the NTENG showed favorable potentiality in wearable intelligent electronics and safeguards.