Synthesis and Characterization of 2D Graphene Thin Films for Optoelectronic Gadgets
Abstract:
This investigation has shown for the first time, the possibility of obtaining high quality 2D graphene thin films for optoelectronic gadgets from the abundant graphite in Nigeria. In the study, synthesis and characterization of graphene from natural graphite and the determination of the electrical conductivity of the thin films were conducted. The samples were characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), field emission scanning electron microscopy and energy dispersive X-ray (FESEM and EDX) to show their structural and compositional features. XRF study showed the mineral compositions as MgO (4.35%), SiO2 (25.14%), SrO (9.73%), CdO (1.99%) and C (15%). XRD pattern indicated perfectly crystallized graphene flakes. Surface morphology by SEM analysis revealed closely packed, layered and spongy structures. EDX studies indicated the elemental composition as Carbon (86.34%), Molybdenum (10.37%), Potassium (2.38%) and Titanium (0.91%). The reduced graphene oxide (RGO)-TiO2 composite thin films displayed glistering surfaces due to the less density of electronic trap states and improved absorption in UV-visible region making them suitable for optoelectronic devices. The resistivity of 1.9592, 12.9366, 2.5419 and 25.1256 s/m were recorded for GO, RGO, GO-TiO2 and RGO-TiO2 thin films. The study has revealed that graphite and its products (GO/RGO) are of high quality. They can be produced for academic research and industrial integration at a lower cost compared to the imported types without detailed characterization systems into African market.
