Synthesis, Structural, and Optical Characterization of ZnO/SnO<sub>2 </sub>Nanocomposites Thin Films Prepared by Spin Coating and Pulse Laser Deposition

ZnO/SnO2 nanocomposite thin films are prepared on glass substrates by spin coating and pulsed laser deposition (PLD) techniques, utilizing various ZnO/SnO2 ratios. The fabricated thin films are exposed to annealing at 300°C to improve their crystallinity. The surface morphology, crystalline structure, and optical properties of the produced ZnO/SnO2 nanocomposite thin films are examined. The FESEM pictures of ZnO and ZnO/SnO2 nanocomposite thin films fabricated via the spin coating process demonstrated an increase in particle size from 11 to 18 nm when the ZnO ratio increased from 50% to 90%. The minimum particle size for samples generated via PLD was 6.5 nm, achieved with a ZnO:SnO2 ratio of 70:30. The XRD results indicated that the ZnO and ZnO/SnO2 nanocomposite thin films, prepared via spin coating and PLD methods, exhibited the hexagonal wurtzite structure of ZnO and the tetragonal structure of SnO2. The optical energy gap of pure ZnO produced by both methods was 3.2 eV, which increased to 3.8 eV for 50ZnO/50SnO2 nanocomposite thin films prepared using the spin coating method. The energy gap of 70ZnO/30SnO2 nanocomposite thin films was 3.7 eV when employing the PLD method.