The effect of sintering atmosphere on colossal permittivity in W+Mg/Al co-doped TiO2 ceramics

Dielectric Properties of Colossal-Dielectric-Constant Na1/2La1/2Cu3Ti4O12 Ceramics Prepared by Spark Plasma Sintering

“…Intensive studies on CP materials during the last two decades have given rise to several material families with CP properties. The titanate families such as CaCu 3 Ti 4 O 12 (CCTO) [ 2 , 3 , 4 ], doped TiO 2 , and their derived ceramics [ 5 , 6 , 7 , 8 , 9 , 10 , 11 , 12 ] are still attracting the attention of researchers. Generally, the structural, electrical, and dielectric properties of CP materials are found to be sensitive to the powder synthesis, calcination, and sintering methods and conditions.…”

The origin of dielectric relaxation behavior in TiO2 based ceramics co-doped with Zn2+, W6+ ions under a N2/O2 sintering atmosphere

“…Compared to ZWTO x -N 2 and ZWTO x -O 2 ceramics, it is worth noting that the CP performance of ZWTO x ceramics was only obtained by sintering under a nitrogen atmosphere. Wei et al 36 reported that the Mg 2+ , W 6+ co-doped TiO 2 ceramics needed to be sintered under a nitrogen atmosphere to obtain CP performance as well, but the reason is not clear. In our case, as shown in Fig.…”

“…These activation energies are approximate to activation energies (E g E 0.72-1.72 eV) of oxygen vacancies relaxation in Ag + /W 6+ or Mg 2+ /W 6+ co-doped rutile TiO 2 ceramics. 24,36 Therefore, the dielectric relaxation process in the region of high temperature can be attributed to the activation of oxygen vacancies.…”

Giant Dielectric Properties of W6+-Doped TiO2 Ceramics

“…If so, can also be produced by the W 3+ doping ions. Usually, oxygen vacancies in co-doped TiO 2 systems can be produced by acceptor doping (e.g., In, Ga, Sc, and Mg) [ 8 , 30 , 35 ]. Thus, as this work has no acceptor dopant, the oxygen vacancies in WTO ceramics can only be due to the sintering process.…”

“…One of the most interesting giant dielectrics of TiO 2 -based ceramics is A/W 6+ co-doped TiO 2 ceramics [ 28 , 29 , 30 ]. For example, Ag + /W 6+ co-doped TiO 2 (AWTO) ceramics exhibited a high ε′ > 10 4 and low tanδ (<0.05).…”