Theoretical study on rotary-sliding disk triboelectric nanogenerators in contact and non-contact modes

The triboelectric nanogenerator (TENG) has emerged as a new and effective mechanical energy harvesting technology. In this work, a theoretical model for a rotary-sliding disk TENG with grating structure was constructed, including the dielectric-to-dielectric and conductor-to-dielectric cases. The finite element method (FEM) was utilized to characterize the fundamental physics of the rotarysliding disk TENG working in both contact and non-contact modes. The basic properties of disk TENG were found to be controlled by the structural parameters such as tribo-surface spacing, grating number, and geometric size. From the FEM calculations, an approximate V-Q-alpha relationship was built through the interpolation method, and then the TENG dynamic output characteristics with arbitrary load resistance were numerically calculated. Finally, the dependencies of output power and matched resistance on the structural parameters and rotation rate were revealed. The present work provides an in-depth understanding of the working principle of the rotary-sliding disk TENG and serves as important guidance for optimizing TENG output performance in specific applications.