Dry lubrication of friction on ferroelectric BiFeO3 film

Abstract

Epitaxial BiFeO3 film shows excellent ferroelectric properties, which is not only studied extensively in magnetoelectric modulation but also shows good tribological performance. In our experiment, we find that the surface of BiFeO3 film can be more lubricant with the application of bias voltages or stress through the AFM probe with a reduction (up to similar to 40%) of the friction between the sample and the probe tip. Based on the Prandtl-Tomlinson model, the mechanism of the dry lubrication on BiFeO3 film originates from the reduction of van der Waals force between sample surface and probe tip. The findings here could be advantageously used in promoting the performance and durability of Micro/Nano Electromechanical devices based on ferroelectric thin films.