Structural and Optical Characterization of Cerium Dioxide Thin Films Prepared and Doped with Carbon Nanotubes by Pulsed-Laser Deposition

Abstract

Thin films of pure cerium oxide (CeO₂) and CeO₂-doped with carbon nanotubes (CNTs) at (0.1, 0.3, and 0.5 wt.%) were fabricated on glass substrates using pulsed laser deposition (PLD). X-ray diffraction (XRD) confirmed polycrystalline films with preferred (111) orientation, and higher CNT doping resulted in broader peaks, indicating reduced crystallite size. Atomic force microscopy (AFM) and scanning electron microscopy (FE-SEM) revealed that increased doping decreased grain size and surface roughness, with mostly homogeneous grain distribution and minor agglomeration. UV–Visible spectroscopy showed decreased absorbance and a widening of the energy band gap from 2.71 eV (pure) to 3.14 eV (0.5 wt.% CNTs). These structural and optical modifications highlight the effectiveness of CNTs incorporation in tuning CeO₂ thin film properties. The observed changes suggest promising potential for tunable optical coatings, enhanced photocatalytic activity, and advanced gas sensing applications.