Local analysis of the grain and grain boundary contributions to the bulk dielectric properties of Ca(Cu 3−y Mg y )Ti 4 O 12 ceramics: Importance of the potential barrier at the grain boundary

Improved giant dielectric properties of CaCu3Ti4O12via simultaneously tuning the electrical properties of grains and grain boundaries by F− substitution

“…This gives rise to a stronger intensity of the polarization at internal insulating interfaces, leading to an increase in 3 0 . The giant dielectric properties of CCTO ceramics were rst reported by Subramanian et al 6 There are further several reports of dopant cations substituted into CCTO ceramic such as Sr 2+ , 23 La 3+ , 7 Ni 2+ , 27 Mg 2+ , 9,[28][29][30] Zn 2+ , 31,32 Ga 3+ , 14 Zr 4+ , 33,34 Sn 4+ , 11 Nb 5+ , 8 Ta 5+ (ref.…”

Improved dielectric properties in A′‐site nickel‐doped CaCu3Ti4O12 ceramics

“…The CaCu 2.9 La 0.2/3 Ti 4 O 12 ceramics exhibit high permittivity and low dielectric losses (ε≈7500 and tanδ≈0.05) . Ca(Cu 3− y Mg y )Ti 4 O 12 ceramics show very high dielectric permittivity values (3.35×10 4 ) and relatively low dielectric losses (<0.06) at room temperature and 1 kHz when mixed with 1% MgO . CaTiO 3 ‐ and SrTiO 3 ‐doped CCTO ceramics have also shown similar effects; although the relative dielectric permittivity remained greater than 10 4 , the observed dielectric losses (>0.15) were still excessive.…”

Structural, microstructural, dielectric and ferroelectric properties of BaTiO3-based ceramics

“…Calcium copper titanate (CaCu 3 Ti 4 O 12 , CCTO) is a non-ferroelectric perovskite type material, possessing a gigantic value of ε r at RT. This system shows the high value of ε r ∼ 10 4 -10 5 , which is independent of fre-quency (10 2 -10 6 Hz) and is almost constant in the 100-600 K temperature range [9][10][11][12]. CCTO ceramics neither exhibit any phase transition nor a crystal structure change in the temperature range of 35-1273 K [6].…”