The universal model for metal-semiconductor tribovoltaic nanogenerators

Metal-semiconductor sliding tribovoltaic nanogenerators (MS-TVNGs) represent a promising energy harvesting technology that converts mechanical energy into direct current (DC) through dynamic Schottky junction. Although p-n junction-based TVNGs have been investigated in prior studies, metal-semiconductor configurations still lack a complete theoretical foundation. Herin, a comprehensive theoretical model is developed for MS-TVNGs, demonstrating their mechanical-to-electrical energy conversion mechanism due to tribovoltaic effect. The proposed framework unifies semiconductor and circuit principles, which elucidates that synergistic tribovoltaic-contact effects at the interface creating electron-hole pairs that are swept by the built-in field to generate current unaffected by sliding direction. Additionally, theoretical results reveal wide-bandgap semiconductors yield higher voltages, whereas increased doping and generation rates boost current, establishing clear design principles for maximizing power density. COMSOL multi-physics simulations incorporating semiconductor transport, circuit coupling, and moving mesh enable performance optimization through material selection, geometry design, and mechanical excitation. This work provides fundamental principles and practical guidelines for the development of high-efficiency tribovoltaic energy harvesting systems.