# Influence of vanadium doping on the processing temperature and dielectric properties of barium bismuth niobate ceramics

Karthik, C and Varma, KBR (2006) Influence of vanadium doping on the processing temperature and dielectric properties of barium bismuth niobate ceramics. In: Materials Science and Engineering: B, 129 (1-3). pp. 245-250.

Barium bismuth vanadium niobate, $BaBi_2(Nb_1_-_xV_x)_2O_9 (0 \leq x \leq 0.1)$ ceramics were fabricated from the powders prepared via solid state reaction route. The single phase layered perovskite structure was preserved up to 5 at% (x = 0.05) of vanadium. The addition of $V_2O_5$ substantially improved the sinterability associated with high density (96%) which was otherwise difficult in the case of pure $BaBi_2Nb_2O_9$ (BBN). The sintering temperature was significantly reduced from 1100 to 900 °C. The scanning electron microscopic (SEM) studies revealed the transformation of a porous microstructure to a well-packed platy grained with negligible inter-granular porosity. The dielectric constant of BBN ceramics at both room temperature and in the vicinity of the temperature of dielectric maximum $(T_m)$ has increased significantly with increase in vanadium content and the loss remained almost constant. The$T_m$ increased with increase in $V_2O_5$. For instance, there was an upward shift of about 25 °C in $T_m$ for 5 at% (x = 0.05) vanadium-doped BBN. Interestingly, the diffuseness $(\gamma)$ in the phase transition was found to decrease with increase in vanadium doping level.