Dielectric properties of CaCu3Ti4O12 (CCTO) doped with GeO2

Dielectrics Properties and Temperature Dependence of Electron Spin Resonance of Doped Molybdenum CCTO

“…It explains that Mo is preferentially returned in the CCTO structure. At this temperature, CCTO doped with molybdenum has the same effect on the grain growth like GeO 2 and V 2 O 3 content obtained in previous studies [11,13]. (Figure 3).…”

“…We observed that for a given frequency, dielectric constant and dielectric loss increase with the molybdenum content ( Figure 4A). This result was observed [10][11][12] for sintering temperatures of various samples doped below 1050°C. The result is in agreement with the theory IBLC which provides an increase in the permittivity when the grain size increases.…”

“…Authors also report the influence of different doping CCTO solid phase. Thus, while the addition of compounds such as TeO 2 , Cerium, Cesium, and Eu 2 O 3 greatly reduce permittivity material [7][8][9], oxides such as P 2 O 5 , GeO 2 , Lu 2 O 3 and V 2 O 3 increase the dielectric constant [10][11][12][13]. When doping is carried out by partial substitution of Ca or Ti sites, we have generally a reduction of the permittivity of the material by substitution on the sites of the first one (Gd et Pr) [14,15] and an increase on the sites of the second one (Nb, Fe, Co, Ni) [16][17].…”

Dielectric and Nonohmic Properties of CaCu3Ti4O12/SrTiO3 Ceramics

“…11,13 Another proposed approach for reducing the dielectric loss is to combine the high-dielectricconstant material with another insulating oxide with low tangent loss to improve the final material characteristics, e.g., GeO 2 , Cr 2 O 3 , and CaTiO 3 . [15][16][17] These results suggest that the appropriate amount of dopant can give rise to an increase of the GB resistance, which contributes to low dielectric loss. GBs are the main source of internal barrier layers in CCTO ceramics, and hence characterization of the GBs of CCTO ceramics is very important.…”

“…The presence of CuO liquid phase in CCTO and BaTiO 3 -based ceramics has been acknowledged as the main parameter promoting grain growth and ceramic densification because of its low melting point and liquid-phase effect. 11,15,22 Based on these results, a small amount of Sr 2+ entering the lattice of CCTO should enhance segregation of Cu-rich phase and promote grain growth since ST has a relatively high melting point, over 2000°C. Furthermore, a small additional amount of ST also assists in inducing better contact between neighboring grains and enhancing the mobility of GBs.…”