The effects of combustion agents on the formation of Bi-based compounds synthesized using the soft combustion method

摘要

In this work, 20% Pr doped bismuth sodium titanate (PBNT) powders were synthesized using the soft combustion technique. Three combustion agents; polyethylene glycol 200, citric acid and glycine with 0.2, 2.0 and 5.0 mol were used to aid combustion process. A single phase PBNT was obtained with the addition of 5 mol.% citric acid. For most compounds, secondary phases presence such as Bi_4Ti_3O_(12) and Bi_2Ti_2O_7. In general, crystallite size increased with increasing sintering temperature that was due to diffusion of ions at high temperature. Dielectric properties increased with increasing densities. The optimum properties were obtained for PBNT synthesized using 5 mol.% citric acid sintered at 1100°C for 3 hours which gave the highest dielectric constant (1153.20), acceptable loss tangent (0.1074) and high relative density (95.03).