Graphene Growth and Carbon Diffusion Process during Vacuum Heating on Cu(111)/Al₂O₃Substrates

Abstract

In this study, the behavior of carbon atoms in the annealing/cooling process of graphene/Cu(111) substrates is investigated using photoelectron spectroscopy and secondary ion mass spectroscopy. After the growth of graphene on Cu(111) surfaces, Cu2O was formed at the graphene/Cu interface during transportation through air atmosphere. The Cu2O layer completely disappeared by vacuum annealing at 500 °C. Graphene was decomposed and carbon atoms diffused into the Cu substrate by further elevation of annealing temperature to 950 °C. When the sample was cooled down, the carbon atoms did not segregate on the surface and remained in the Cu substrate. This result indicates the carbon atoms easily diffuse into Cu substrates in vacuum annealing while the amount of diffused carbon atoms in the thermal chemical vapor deposition (CVD) process is smaller, suggesting that the barrier layer, which prevents the diffusion of C atoms, exists on Cu surfaces in the graphene CVD growth.

Helium diffraction and acoustic phonons of graphene grown on copper foil

“…This means that the surface quality deteriorates when heating above 650 K. Recently it has been reported that Cu 2 O is formed at the graphene/Cu(111) interface during exposure to ambient conditions, and that it disappears when heating above ca. 650 K [27]. This is consistent with our observation of a pressure increase when heating the sample at 650 K, which might be due to oxygen desorption.…”

A high energy density asymmetric supercapacitor utilizing a nickel phosphate/graphene foam composite as the cathode and carbonized iron cations adsorbed onto polyaniline as the anode

“…34 and pp* (satellite peak/electrons transition) bonding respectively. [35][36][37] In Fig. 2(f), all tted peaks reveal the sp 2 hybridization property of GF, traces of oxygen content present in GF and the p-p* electrons transition which enhances the carbon to carbon bonds in graphene and conrms the high quality of GF.…”

Roles of Oxygen and Hydrogen in Crystal Orientation Transition of Copper Foils for High-Quality Graphene Growth

“…It is noted that graphene can protect the surface of Cu substrate from oxidation in a short term due to its impermeability and thermal/chemical stability4546. However, the Cu oxidation can still occur4748 because the carbon-metal interaction can accelerate electrochemical oxidation of Cu substrate through galvanic corrosion4649.…”