Temperature effect on hydrogenated amorphous carbon leading to hydrogenated graphene by pulsed laser deposition

A direct synthesis of hydrogenated graphene at a reduced temperature of 400° C using pulsed laser ablation technique is reported. Here, we have investigated the effect of the substrate temperature. Therefore, hydrogenated carbon thin films were elaborated under the same conditions of laser fluence and CH4 pressure but at different substrate temperatures ranging from room temperature to 600 °C. The Raman and X-ray photoelectron spectroscopy revealed a structural change induced by the substrate temperature increase. Indeed the elaborated thin films evolved from amorphous carbon to hydrogenated graphene as the substrate temperature increases. The elastic recoiled detection analysis and the Rutherford backscattering measurements indicated a decrease in the hydrogen content as well as a thickness reduction along with the substrate temperature increase. We have concluded that the structural change can be ascribed to the increase in the species mobility during the growth.