Study on the temperature dependence of graphite synthesis on the surface of Al₂O₃ nanoparticles by thermal chemical vapor deposition

The effect of temperature on the synthesis of graphite on the surfaces of aluminum oxide (Al₂O₃) nanoparticles by using thermal chemical vapor deposition was investigated. Graphite coated the entire surfaces of the Al₂O₃ nanoparticles. The effect of temperature on the graphite was confirmed by varying the temperature from 800 to 1100 °C in 100 °C increments. Changing the synthesis temperature induced changes in the properties of the surface graphite and the Al₂O₃ nanoparticles. X-ray photoelectron spectroscopic (XPS) analysis confirmed that Al₂O₃ nanoparticles reacted with carbon gas as the synthesis temperature was increased. Carbon gas with Al₂O₃ nanoparticles was observed began at 900 °C and to stop at 1100 °C. These differences confirmed that the formation of graphite on the Al₂O₃ nanoparticles' surfaces was temperature dependent. Analyses using Raman spectroscopy and transmission electron microscopy (TEM) were conducted to compare the states of the synthesized graphite.