A contact-key triboelectric nanogenerator: Theoretical and experimental study on motion speed influence

Harvesting mechanical energy based on the triboelectric and electrostatic concepts is a very new and extremely fast growing technology. The effect of time in which a typical energy generation cycle occurs is deeply studied here. Three set of contact key with nano-structured triboelectric surfaces, each including a magnetic and fingertip driving mechanisms, were developed and studied. The system is represented by an equivalent circuit, validated by finite element method and the relative mathematical description, and then studied by numerical analysis. It is shown how the relative speed of triboelectric surfaces affects the peak instantaneous and the average power, which is related to the electrostatic phase of energy generation. However, evidences show that the contact/release speed may also influence the charge separation amount, i.e. triboelectric phase of energy generation, which needs to be investigated too.