Ta, Lu dual-donor doped SrTiO3 ceramics with colossal permittivity and ultra-low dielectric loss

This study investigates the dielectric properties of Sr 0.985 Lu 0.01 Ti 1- x Ta x O 3 ceramics co-doped with Lu and Ta as dual-donor, which were prepared using a solid-state method and sintered in a nitrogen atmosphere. The XRD results demonstrate that the dual-donor doping of Lu and Ta at Sr and Ti sites, respectively, which will improve the dielectric properties. The optimal dielectric properties were observed when x = 0.01, which the permittivity reaching approximately 220,000 and the dielectric loss is around 0.02. Through XPS and defect chemical analysis, it has been identified that the formation of point defects including , , and Ti 3+ will be produced by sintering in N 2 -atmosphere and the dual-donor doped of Lu 3+ and Ta 5+ . These point defects aggregate into dipole clusters, such as Ti 3+ Ti 3+ , and Ti 3+ , resulting in enhanced EPDD effect and reduced dielectric loss. This work provides valuable insights into the design of advanced dielectric materials with colossal permittivity.