New negative temperature coefficient ceramics in ACu3Ti4O12 (A = Sr, La2/3, Ca, Y2/3) system

Extremely enhanced thermal stability of Y2/3Cu3Ti4O12 ceramics by a Pechini method

“…The value of activation energy ( E a ) is calculated by the dependence of resistance on temperature, which represents the lowest energy required for the reaction to occur, and is listed in Table 4. The activation energy of YCTO‐S is about 0.6 eV, in general agreement with the results reported in the previous work 60 . The activation energy of YCTO‐P is much lower than that of YCTO‐S.…”

“…This greatly affects the possibility of electron hopping to adjacent positions, leading to its higher resistivity. 59 The value of activation energy (E a ) is calculated by the dependence of resistance on temperature, which represents the lowest energy required for the reaction to 60 The activation energy of YCTO-P is much lower than that of YCTO-S. The reduction of the activation energy contributes to the reduction of the energy required for the transition from the normal state to the active state where chemical reactions can easily occur.…”

High Dielectric Constant and Dielectric Relaxations in La2/3Cu3Ti4O12 Ceramics

“…[9,[13][14][15][16][17][18][19][20][21] have been found to have the similar high dielectric constant as CaCu 3 Ti 4 O 12 , which revises the report by Subramanian [2] and brings new questions about the physical origin of dielectric response in ACu 3 Ti 4 O 12 ceramics. Internal barrier layer capacitor (IBLC) effects related to defect structure in grain and grain boundaries have been widely adopted to explain the origin of high dielectric response in these ACu 3 Ti 4 O 12 ceramics [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28].…”