Self-powered multi-parameter sensing system without decoupling algorithm needed based on flexible triboelectric nanogenerator

The rapid development of wireless sensor networks (WSN) and Internet of things (IoT) bring an urgent need for wireless sensor nodes featured with flexibility, self-powering and multi-sensing functionalities. Recently, self -powered sensors based on micro-energy harvesting methods are intensively studied as a potential solution. However, their single sensing function and poor anti-interference capability have become one of the major bottlenecks obstructing their widespread applications and commercialization. This work proposes a flexible textile-based, switch-integrated triboelectric nanogenerator (S-I-TENG), which is able to scavenge mechanical energy and generate an oscillating signal containing sensing information. With a facile circuit configuration based on triboelectric effect, frequency modulation and voltage divider to improve anti-interference capability, external stimulus frequency, capacitive and resistive sensing information with high accuracy can be easily ob-tained and decoded without any complicated calculation or decoupling algorithm required. Results showed that the self-powered multiparameter sensing system has a high sensitivity of 759.47 Hz/%RH and 0.01096/celcius for humidity and temperature sensing, and accuracy of over 94% and 96%, respectively. The S-I-TENG is adhered to an insole to scavenge human walking energy, which is then used to sense the ambient relative humidity, tem-perature, and human walking frequency concurrently and display them in real-time.