The role of hydrocarbon concentration on the synthesis of large area few to multi-layer graphene structures

► Few layer graphene structures were synthesized on a bi-metallic catalyst system utilizing acetylene as the hydrocarbon source. ► Flow rate of acetylene was varied from 4.5 to 6 ml/min. ► The diameter of the graphene structures increased from a few hundred nanometers to a few micrometers. ► The number of layers was also found to be dependent on the hydrocarbon concentration.