Fast densification and electrical conductivity of yttria-stabilized zirconia nanoceramics

Enhanced electrical conductivity of ultrafine-grained 8Y2O3 stabilized ZrO2 produced by two-step sintering technique

“…The coloring of SPS specimens was previously reported as an indicator of reduction process during sintering [14]. Li et al [7] reported higher contribution of the grain boundary resistance (R GB ) to the total resistance (R GB + R Grain ) of the high-pressure sintered nanocrystalline YSZ. The observed higher resistance in grain boundaries was attributed to the impurity phase.…”

“…The higher the diffusion coefficient of the system, the greater the conduction coefficient achieved. It seems, therefore, that an increase in the highly diffuse surface atoms located at the grain boundaries would enhance the ionic conductivity of the specimens [7,8].…”

“…Han et al [2] reported a higher ionic conductivity for YSZ electrolytes with a smaller grain size, while Li et al [7] showed that the activation energy of ionic migration in nanocrystalline samples with grain size of 20-30 nm were about 10% higher than that of microcrystalline ones. Ramamoorthy et al [8] illustrated that the magnitude of the ionic conductivity for (a) lattice, (b) grain boundary and (c) overall system for all yttria concentrations were slightly lower than that for coarser structures.…”

“…Li et al [7] have attributed higher resistance of the grain boundaries to the impurity phase. Mondal et al [3] have reported enhanced specific grain boundary conductivity in nanocrystalline Y 2 O 3 stabilized zirconia.…”

Influence of the urea content on the YSZ hydrothermal synthesis under dilute conditions and its role as dispersant agent in the post-reaction medium

“…3b, d and f) corresponding to the asprepared powders present very broad and weak intensity peaks due to the nano-effect indicating a small domain size. 40 These results are supported by the high specific surface area shown in Table 2 and the primary particle sizes observed by TEM. Comparing the TEM micrographs of the three powders obtained, those synthesized from the SH II,st reaction seem to be the least agglomerated ones.…”