Microstructure and dielectric properties of CaCu3Ti4O12 ceramics by quenching after sintering in low vacuum and thermobaric treatment at 9 GPa

From Synthesis to Applications: Copper Calcium Titanate (CCTO) and its Magnetic and Photocatalytic Properties

“…Each apparatus has its own advantages and unique applications . High pressure and high temperature sintering methods have been recently used to prepare CCTO ceramics …”

“…[51] High pressure and high temperature sintering methods have been recently used to prepare CCTO ceramics. [52,53] In order to study the properties of the CCTO ceramics prepared by thermobaric treatment, Xu et al [52] prepared quenched CCTO at 1000°C/10 min after it had been subjected to a high quasihydrostatic pressure of 9 GPa. Such high pressure and high temperature treatment (HPT) result in significant changes of the crystallochemical parameters.…”

“…Mao et al [53] prepared the Calcium copper titanium oxide (CCTO) ceramics using the following procedure: Ceramics were quenched in air and liquid nitrogen separately after being [50] subjected to sintering in low vacuum and thermobaric treatment (TBT) at 9 GPa and 1000°C for 10 min. The microstructures of the obtained ceramics are shown in Figure 23.…”

Giant dielectric behavior of monovalent cation/anion (Li+, F−) co‐doped CaCu3Ti4O12 ceramics

“…Recently, giant dielectric materials belonging to the family of ACu 3 Ti 4 O 12 compounds have generated considerable interest due to their potential applications for the miniaturization of microelectronic devices, for example, multilayer ceramic capacitors. CaCu 3 Ti 4 O 12 (CCTO) is a popular material among the ACu 3 Ti 4 O 12 compounds because it exhibits a very large dielectric permittivity ( ε ′ ~10 4 ) over a wide temperature range without a detectable phase transition in the temperature range of 35‐100 K . However, a structural phase transition occurred in CCTO ceramics at 726‐732 K .…”

“…Recently, giant dielectric materials belonging to the family of ACu 3 Ti 4 O 12 compounds have generated considerable interest due to their potential applications for the miniaturization of microelectronic devices, for example, multilayer ceramic capacitors. CaCu 3 Ti 4 O 12 (CCTO) is a popular material among the ACu 3 Ti 4 O 12 compounds because it exhibits a very large dielectric permittivity (ε′ ~10 4 ) over a wide temperature range without a detectable phase transition in the temperature range of 35-100 K. [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19] However, a structural phase transition occurred in CCTO ceramics at 726-732 K. [20][21][22][23] Although the origin of the dielectric behavior is currently unclear, it is clearly shown that the microstructure of CCTO polycrystalline ceramic is electrically heterogeneous and comprised of semiconducting and insulating phases. This particular structure is referred to as an internal barrier layer capacitor (IBLC) structure.…”