Tribovoltaic Effect: Origin, Interface, Characteristic, Mechanism & Application

Tribovoltaic effect is a phenomenon of the generation of direct voltage and current by the mechanical friction on semiconductor interface, which exhibits a brand-new energy conversion mechanism by the coupling of semiconductor and triboelectrification. Here, the origin, interfaces, characteristics, mechanism, coupling effect and application of the tribovoltaic effect is summarized and reviewed. The tribovoltaic effect is first proposed in 2019, which has developed in various forms tribovoltaic nanogenerator (TVNG) including metal-semiconductor, metal-insulator-semiconductor, semiconductor-semiconductor, liquid-solid and flexible interfaces. Compared with triboelectric nanogenerator, the TVNG has the characteristics of direct-current, high current density (mA-A cm^-2) and low impedance (Ω-kΩ). The two mainstream views on the tribovoltaic generation mechanism, one dominated by built-in electric fields and the other dominated by interface electric fields, have been elaborated and summarized in detail. The tribo-photovoltaic effect and tribo-thermoelectric effect are also discovered and introduced because they can easily interact with other multi-physical field effects. The TVNGs are suitable for making energy harvesting and self-powered sensing devices for micro-nano energy applications. This paper not only revisit the development of the tribovoltaic effect, but also makes prospects for mechanism research, device fabrication and integrated application, which can accelerate the evolution of smart wearable electronics and intelligent industrial components.