Triboelectric nanogenerators based on transition metal carbo-chalcogenide (Nb₂S₂C and Ta₂S₂C) for energy harvesting and self-powered sensing

Abstract

With burgeoning considerations over energy issues and carbon emissions, energy harvesting devices such as triboelectric nanogenerators (TENGs) are developed to provide renewable and sustainable power. Enhancing electric output and other properties of TENGs during operation is the focus of research. Herein, two species (Nb2S2C and Ta2S2C) of a new family of 2D materials, Transition Metal Carbo-Chalcogenides (TMCCs), are first employed to develop TENGs with doping into Polydimethylsiloxane (PDMS). Compared with control samples, these two TMCC-based TENGs exhibit higher electric properties owing to the enhanced permittivity of PDMS composite, and the best performance is achieved at a concentration of 3 wt. ‰ with open circuit voltage (Voc) of 112 V, short circuit current (Isc) of 8.6 µA and charge transfer (Qsc) of 175 nC for Nb2S2C based TENG, and Voc of 127 V, Isc of 9.6 µA, and Qsc of 230 nC for Ta2S2C based TENGs. These two TENGs show a maximum power density of 1360 and 911 mW m−2 respectively. Moreover, the tribology performance is also evaluated with the same materials, revealing that the Ta2S2C/PDMS composite as the electronegative material presented a lower coefficient of friction (COF) than the Nb2S2C/PDMS composite. Their applications for energy harvesting and self-powered sensing are also demonstrated.