摘要
Doped nano-ceria particulates ((Ce0.9Gd0.1)O2, GDC) were synthesized by hydrothermal processes and dispersed within a matrix of copper-doped bismuth vanadate (Bi2V0.9Cu0.1O5.35, BICUVOX) powder at levels ranging from 0.2 to 4.0 wt.%. The BICUVOX powder was synthesized by a co-precipitation process which resulted in a homogenous, fine-grained powder with an average particle size of ~ 0.6 渭m. The BICUVOX/GDC composite was sintered at temperatures between 675 and 800 掳C for 4 h. The incorporation of the nano-GDC into the BICUVOX ceramic was shown to pin grain boundary mobility, which permitted sintering to high densities while retaining finer grain sizes (1-4 渭m in average size). The low levels of nano-GDC additions were shown to decrease the total conductivity of the BICUVOX electrolytes. Four-point conductivity testing of the BICUVOX/GDC (0.6 wt.%) composite in air showed values of ~ 0.008 S/cm and ~ 0.06 S/m at 300 掳C and 500 掳C, respectively. The average flexure strength of the same composite membrane was measured using a ring-on-ring configuration, and this measurement showed flexural strengths as high as 134.2 MPa. This strength is ~ 60%greater than previously reported values for BICUVOX membranes.