Investigation of Synthesis Methods and Dope Type Effect on Conductivity and Luminescence Properties for CeO2 Compounds

Abstract

The aim of this study is to investigate how the materials synthesized by both methods affect the luminescence and electrical properties. Also, another purpose is to examine the effect of doping types on optics and conductivity. At the end of the synthesis, X-Ray diffractometer (XRD) was used to examine the crystal structure and the possible different phases that may occur, Raman spectroscopy analysis was used to obtain information about the symmetry properties of the formed structure and the appearance of different vibration modes and the degradation (defect) formed in the structure. Photoluminescence (PL) Spectroscopy measurements at room temperature were employed. The peaks in the excitation spectrum at approximately 446 nm (⁵I₈ → ⁵G₆) correspond to the 4f-5d transition of the Ce^{3 +} ion. Specific surface area analysis was performed using Brunauer-Emmett-Teller (BET). FE-SEM image was taken for morphological analysis of the structure. The ionic conductivity of the pelletized powder ceramic undoped CeO₂ and La³⁺, and Ho³⁺ doped CeO₂ electrolyte was measured by impedance spectroscopy. The temperature value of the Ce_0.85La_0.10Ho_0.05O₂ sample synthesized by the high conductivity hydrothermal method was found as 5.64x10^-3 Ω.cm^-1 at 750 with the best conductivity result.