Impedance Spectroscopy Study of Sintering in Bi-Doped ZnO

Solid‐ and liquid‐state sintering kinetics in the (1 – x)ZnO‐xBi2O3 system with 0 ≤x≤ 0.05 over the range 600 ≤T (°C) ≤ 1100 were investigated by impedance spectroscopy. Compositions with x < 0.002 retarded sintering, whereas compositions with x≥ 0.004 accelerated sintering above the eutectic temperature of 740°C. The results could be interpreted in terms of limited solid solubility of Bi2O3 in ZnO (x≃ 0.004 ± 0.002), solid‐state sintering in the subsolidus, and liquid‐state sintering above the solidus. A phase diagram for the ZnO‐rich end of the system is proposed, based on these results.