Researchers at the University of Aveiro, Portugal, the Institute of Natural Sciences, Russia and the Instituto de Fisica, Brazil observed a strong piezoelectric activity of single-layer graphene (SLG) deposited on Si/SiO2calibration grating substrates. The scientists perceive the piezoelectric effect to be strong enough to enable future applications like graphene-based actuators, sensors and other electronic components based on the direct and converse piezoelectric effects.
The researchers performed an experimental study of single-layer graphene (SLG) deposited on SiO2 calibration grating substrates by piezoresponse force microscopy (PFM) and confocal Raman spectroscopy. Piezoelectric activity was mainly observed on the supported graphene regions where van der Waals and/or chemical interaction between the SiO2 surface and graphene layer can induce an anisotropic strain and detectable PFM signal. The piezoelectric activity in the graphene layers was attributed to the chemical interaction of graphene atoms with underlying oxygen from SiO2 substrate. Piezoelectric effect was found to be relatively high, more than twice that of the best piezoelectric ceramics such as modified lead zirconate titanate.