Table 1.
Crystalline phases of (Bi2O3)80Ta20 as a function of milling time under different oxygen environments.
| Milling Condition | Milling Time | Crystalline Phases |
|---|---|---|
| Inside Ar-filled glove box | 5 min | α-Bi2O3 (84.6%) * + Ta (15.4%) |
| 10 min | α-Bi2O4 (8.1%) + α-Bi2O3 (13.2%) + Bi (23.4%) + δ-Bi3TaO7 (52.8%) + Ta (2.5%) | |
| 15 min | α-Bi2O4 (8.3%) + α-Bi2O3 (3.8%) + Bi (44.4%) + δ-Bi3TaO7 (41.5%) + Ta (2.0%) | |
| 20 min | α-Bi2O4 (8.7%) + Bi (47.8%) + δ-Bi3TaO7 (41.4%) + Ta (2.0%) | |
| 25 min | α-Bi2O4 (8.7%) + Bi (49.9%) + δ-Bi3TaO7 (40.0%) + Ta (1.4%) | |
| 30 min | α-Bi2O4 (8.2%) + Bi (52.9%) + δ-Bi3TaO7 (37.4%) + Ta (1.5%) | |
| 1 h | α-Bi2O4 (8.8%) + Bi (60.3%) + δ-Bi3TaO7 (28.6%) + Ta (2.3%) | |
| 3 h | α-Bi2O4 (9.4%) + Bi (69.7%) + δ-Bi3TaO7 (18.8%) + Ta (3.1%) | |
| Under air | 5 min | α-Bi2O4 (5.5%) + α-Bi2O3 (13.0%) + Bi (21.2%) + δ-Bi3TaO7 (58.7%) + Ta (1.6%) |
| 10 min | α-Bi2O4 (4.5%) + α-Bi2O3 (10.0%) +Bi (33.8%) + δ-Bi3TaO7 (50.5%) + Ta (1.2%) | |
| 15 min | α-Bi2O4 (5.3%) + Bi (39.5%) + δ-Bi3TaO7 (54.5%) + Ta (0.7%) | |
| 20 min | α-Bi2O4 (3.0%) + Bi (38.0%) + δ-Bi3TaO7 (58.6%) + Ta (0.4%) | |
| 25 min | α-Bi2O4 (1.8%) + Bi (42.0%) + δ-Bi3TaO7 (54.1%) + Ta (2.1%) | |
| 30 min | α-Bi2O4 (5.1%) + Bi (52.8%) + δ-Bi3TaO7 (40.6%) + Ta (1.5%) | |
| 1 h | α-Bi2O4 (2.9%) + Bi (56.0%) + δ-Bi3TaO7 (40.3%) + Ta (0.8%) | |
| 3 h | α-Bi2O4 (2.7%) + Bi (71.9%) + δ-Bi3TaO7 (25.4%) |
Note: *: the percentage of individual phase is given in the bracket