Investigating the effect of nanoscale triboelectrification on nanofriction in insulators

Nanofriction and nanoscale triboelectrification is a universally existing phenomenon and important in many branches of nanotechnology, but how the nanoscale triboelectrification affects the nanofriction during the relative sliding at the contact interface is not fully investigated. Here, nanoscale triboelectrification and nano friction on the insulating SiO2 surface were investigated with atomic force microscopy (AFM) and scanning Kelvin probe microscopy. By the AFM tip sliding on the SiO2 surface, both triboelectric charges and nanofriction were investigated with the applied load, sliding cycle, and external electric field. Whether the tribocharges on the SiO2 surface were negative or positive, the nanofriction increases with the enhanced tribocharge density by nanoscale triboelectrification, while decreases with the reduced tribocharges by charge diffusion. The change of nanofriction correlates strongly with the variation in tribocharge density due to the tribocharge induced excess electrostatic interactions at the sliding interface. These findings not only add to our understanding of the role of nanoscale triboelectrification on nanofriction, but also help to control energy dissipation of sliding nanofriction, which is also important in many branches of nanotechnology, such as data storage and nanoelectromechanical system.

Automated summary

The study investigates nanoscale triboelectrification and nanofriction on insulating SiO2 surface using AFM and scanning Kelvin probe microscopy. It finds that nanofriction increases with enhanced tribocharge density and decreases with reduced tribocharges due to charge diffusion. These findings provide insights into the role of nanoscale triboelectrification on nanofriction and could help control energy dissipation in sliding nanofriction.