Nowadays, nature-inspired structural colorization takes increasing attention due to its exceptional optical properties. One-dimensional (1-D) photonic crystals are new kind of optical materials which can be used to obtain structural colorization. In recent years many studies carried out about 1-D photonic crystals because of its simplicity and cost-effectiveness. In this study, CuO/TiO2 multilayer thin films were prepared by sol-gel spin coating technique on boron silicate substrate. To understand the effect of rare-earth element doping on structural colorization, Cerium and Europium ions doped CuO layers were prepared with different dopant concentrations. Structural and morphological properties of 1-D photonic crystals were investigated by X-ray diffraction (XRD), Scanning electron microscopy (SEM) and optical microscopy. Obtained results show that CuO/TiO2 multilayer thin films with different Cerium and Europium concentrations were successfully prepared. Additionally, red and green colorization was achieved with different type and concentrations of dopant elements and more vivid colors were obtained as a result of increment in dopant concentration.

Keywords - Photonic Crystal, Thin film, Sol-gel, Rare-earth Doping, Structural Color

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