Impact of thermal treatment on graphene films synthesized via interfacial trapping technique

Large variety of graphene applications in science and technology justify different methods to obtain pure graphene films. Among these methods, Woltornist et.al., ACS Nano 7, 7062 (2013) obtained promising results by pulverizing ultrapure graphite in water/n-heptane mixture to form continuous films on glass substrate. We report here subsequent steps of studying this method with different substrates and also of application of annealing (100^o-600^o, in air and in a vacuum) on the physical properties of these films. As can be deduced from Raman spectra, the quality of graphene films is enhanced in certain temperature range. We complemented Raman mapping by characterizing the morphology of films using scanning electron microscopy. Other instrumentation techniques have also been used to affect and study the physical properties of these films. Overall, the simplicity of the method and the quality of the film reveal potential areas of applications in microelectronics.