Effect of process parameters on kinetics and characteristics of graphene produced by electrochemical exfoliation of graphite foil

Electrochemical exfoliation of graphene is emerging as an efficient process owing to its high scalability. However, most studies are conducted at high voltages, resulting in multi-layer graphene with high defect concentrations. In this study, multilayer graphene was synthesized via electrochemical exfoliation of graphite foil using KOH solution at various processing conditions. The effects of various process parameters, including molarity, electrode spacing, electrolyte temperature, current density, and stirring speed, on the kinetics of graphene exfoliation were studied. The as-synthesized graphene was characterized using various techniques. TEM, AFM, and Raman spectroscopy confirmed the synthesis of multilayer graphene with relatively low defect concentrations. A proof-of-concept study showed that tungsten oxide nanopowder exhibits improved NO 2 gas-sensing performance when mixed with graphene. The minimum concentration of NO 2 detected at room temperature using tungsten oxide mixed with graphene nanoplatelets was 0.75 ppm.