Tactile electronic skin to simultaneously detect and distinguish between temperature and pressure based on a triboelectric nanogenerator

Tactile electronic skin (e-skin) aims to mimic the functions of skin, which could have profound implications for areas including medical care, prosthetics and robotics. However, it faces a great challenge to simultaneously detect and distinguish between multiple stimuli by a single device. Here, a tactile e-skin that can simultaneously detect and distinguish between temperature and pressure in real time is developed, based on a single-electrodemode triboelectric nanogenerator (TENG) with a specially prepared thermoresistive electrode combining BiTO and rGO. The TENG based tactile e-skin outputs voltage in response to pressure (superior sensitivity of 5.07 mV/Pa) and its electrode resistance changes in response to temperature (thermal sensitivity beta(25)(/100): 1024 K, temperature coefficient of resistance: 1.15%/K at 25 degrees C, range: 25-100 degrees C). The pressure sensing performance maintains stable with varying temperatures and the temperature sensing performance is undisturbed under pressure. The tactile e-skin also demonstrates excellent sensing reproducibility and durability. When the e-skin is mounted on the human body, it can monitor and distinguish between temperature and pressure with the two signals imposing no interference on each other. This work provides new mutes for wearable sensing and sheds new light on the development of electronic skin.