Integrated Piezo-Triboelectric Nanogenerators-Based Self-Powered Flexible Temperature and Pressure Sensor

Abstract

Efficient harvesting of ubiquitous ambient mechanical energy using various types of nanogenerators (NGs) has attracted considerable interest in recent years. Herein, we present a textile triboelectric nanogenerator (T-TENG) using Polytetrafluoroethylene (PTFE) and Nylon based counter-surfaces in fabric form (both fixed to conductive fabric electrodes). T-TENG performance is enhanced by exposing PTFE film with Argon plasma. The output voltage of the plasma treated devices increased by a factor of ~10, and their short circuit current density increased by a factor of ~9 (compared to pristine non-plasma treated devices). Additionally, we demonstrate that the fabricated T-TENG can be used as a self-powered temperature sensor, tested in the 25-90 °C range. The T-TENG output voltage decreased linearly with increasing temperature exhibiting a sensitivity of ~ 1%/(°C). Further, we integrated a flexible piezoelectric nanogenerator (PENG) on top of the T-TENG to detect the contact forces. The PENG output is also used to compensate the pressure dependent output of TENG underneath, and allows distinct temperature and pressure measurements. The excellent results observed here show the potential of T-TENGs for use as self-powered sensors in applications such as health monitoring, wearables and interactive systems.