Properties and intergranular phase analysis of a ZnO–CoO–Bi2O3 varistor

Microstructure and electrical properties of Y(NO3)3·6H2O-doped ZnO–Bi2O3-based varistor ceramics

“…The sintered samples were lapped and polished and then the final samples were about 10 mm in diameter and 1.0 mm in thickness. The bulk density of the samples was measured in terms of their weight and volume [25,26].…”

Hierarchical Growth of ZnO Particles by a Hydrothermal Route

“…[1][2][3][4][5] Conventional uses of ZnO include varistors, piezoelectrics, sensors, photocatalysts, cosmetics and sunscreens. 6,7,8 Zinc oxide typically crystallises with the wurtzite hexagonal structure. 9 Physical and electronic properties of ZnO are dependent on particle size and morphology.…”

Size Effect on Properties of Varistors Made From Zinc Oxide Nanoparticles Through Low Temperature Spark Plasma Sintering

“…4d), metallic bismuth turned into gBi 2 O 3 or Bi 38 ZnO 58 . The main bismuth-rich phase usually found in varistor ceramics made by classical sintering is the b-Bi 2 O 3 phase, [10,16] but the presence of d, g, and a phases are also reported in some studies, depending on the additives and thermal processing conditions. [17][18][19][20] At a temperature of 650 8C, bismuth oxide and zinc oxide do not form the eutectic so that no additional sintering and no grain growth occur.…”

“…Usually, the amount of bismuth oxide used for varistor ranges from 0.5 to 1 mol%. [14,16,26] The surface to volume ratio is considerably higher in the case of nanoparticles when compared to micrometric powders. Therefore, we adapted the bismuth precursor quantity accordingly and focused our study on 0.08 M equivalents of bismuth precursor for the synthesis of the particles which corresponds to 3.7 mol % Bi 2 O 3 .…”