Sustainable Triboelectric Nanogenerator from Abalone Shell Powder for Self-Powered Humidity Sensing
Yunsook Yang, Farhan Akhtar, Shahzad Iqbal, Muhammad Muqeet Rehman, Woo Young Kim
Abstract
Self-powered sensors are critically important for IoT, yet most rely on synthetic polymers that lack environmental sustainability. This work presents a triboelectric nanogenerator (TENG) made from marine biowaste which operates as both an energy generator and humidity sensor. Abalone shell powder (ASP) majorly composed of calcium carbonate (CaCO3) was used as its tribopositive layer in combination with polytetrafluoroethylene (PTFE) as tribonegative layer. The developed ASP-TENG device generated 410 V peak to peak open-circuit voltage (VOC) and 2.79 W·m−2 peak power density at an operating frequency of 4 Hz. These obtained results match or surpass existing biowaste-based TENGs. ASP-TENG efficiently worked as a self-powered humidity sensor because its output voltage decreased steadily from 410 V to 176 V in response to an increase in relative humidity (%RH) from 40% to 80% (decreases of 5.8 V for every 1%RH). The triboelectric charges become screened by water molecules that adsorb onto the porous CaCO3 surface which leads to faster leakage current. This work demonstrates a sustainable method to create TENGs with multiple functions while developing environmentally friendly sensing systems for environmental tracking and sustainable energy harvesting.