Investigation of structural, photo-luminescence and self-cleaning properties of thin layers of GO-ZnO and GO, GO-Ag and composite bilayer of GO-ZnO/GO-Ag prepared by spray pyrolysis method

The synthesis of graphene oxide-zinc oxide, graphene oxide- silver, graphene oxide thin layers, and graphene oxide-zinc/graphene oxide-silver bilayer was done using a method called spray pyrolysis. Characterization of the synthesized layers was done by X ray diffraction, transmission electron microscope, atomic force microscope, photo-luminescence, FTIR and BET analyses. Based on the TEM images, the given nano-composites are formed and GO can be a suitable platform for the growth of silver and ZnO nano-particles and prevents their accumulation. According to the AFM images, GO-ZnO/GO-Ag sample has the lowest roughness. PL spectrum showed a broad emission peak for GO-Ag layer at a wavelength of approximately 550 nm, which is consistent with the reported band gap of 3.6eV. From BET results, the surface area was obtained 4 m2g-1 and 14 m2g-1, for GO and GO-Ag samples respectively which were greater than the similar work. The pore diameter of GO-ZnO sample was obtained equal to 16.5 nm, indicating the superiority of the meso-holes in GO-ZnO sample. Also, the surface area of GO-ZnO/GO-Ag bilayer was around 3.6 times larger than the surface area of ZnO. The contact angles of droplet with the surface in GO, GO-Ag, GO-ZnO, GO-ZnO/GO-Ag samples are 55.02, 60.24, 31.28, 56.35, respectively.