Effect of current pulse pattern on Ce3+-doped (Gd,Lu)3Al5O12 ceramics fabricated by spark plasma sintering

To investigate the effect of the current pulse pattern on the PL emission characteristics, Ce3+:(Gd,Lu)3Al5O12 ceramics were fabricated by the SPS process on separators (BN powder and C paper) and current pulse patterns (DC and BC modes). In the DC mode of the SPS process, the reduction process caused by the carbon atmosphere occurred relatively more actively than in the BC mode. During annealing, the oxidation process also excessively occurred compared to the BC mode, and consequently, the Ce3+ fraction in the DC mode was significantly reduced. In the present work, the Ce3+ fraction served as the most dominant factor affecting the PL emission characteristics than the microstructure and dopant distribution. As a result, despite the discrepancy in the relative density of about 1.2%, the PL emission characteristics were improved because the Ce3+ fraction of only 0.4% was high. © 2023 Elsevier GmbH