Dry lubrication of friction on ferroelectric BiFeO 3 film

Abstract

Epitaxial BiFeO 3 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 BiFeO 3 film can be more lubricant with the application of bias voltages or stress through the AFM probe with a reduction (up 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 BiFeO 3 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.