High temperature and current density induced degradation of multi-layer graphene

We present evidence of moderate current density, when accompanied with high temperature, promoting migration of foreign atoms on the surface of multi-layer graphene. Our in situ transmission electron microscope experiments show migration of silicon atoms at temperatures above 800 °C and current density around 4.2 × 10⁷ A/cm². Originating from the micro-machined silicon structures that clamp the freestanding specimen, the atoms are observed to react with the carbon atoms in the multi-layer graphene to produce silicon carbide at temperatures of 900-1000°C. In the absence of electrical current, there is no migration of silicon and only pyrolysis of polymeric residue is observed.