Reduction and Phase Transformation of Ce-Doped Zirconolites
Abstract
:1. Introduction
2. Materials and Methods
2.1. Fabrication of Zirconolite
2.2. Reduction in Zirconolite
2.3. Characterization of Reduced Zirconolite
3. Results
3.1. Fabrication of Zirconolite
3.2. Reduction in Zirconolite
3.3. Characterization of Reduced Zirconolite
4. Discussion
4.1. Zirconolite Fabrication
4.2. Reduction in Zirconolite
4.3. Characterization of Reduced Zirconolite
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Conflicts of Interest
References
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Ce | Al | Composition |
---|---|---|
x = 0 | - | CaZrTi2O7 |
x = 0.2 | - | CaZr0.8Ce0.2Ti2O7 |
x = 0.35 | - | CaZr0.65Ce0.35Ti2O7 |
y = 0.2 | y = 0.2 | Ca0.8Ce0.2ZrTi1.6Al0.4O7 |
y = 0.35 | y = 0.35 | Ca0.65Ce0.35ZrTi1.3Al0.7O7 |
Composition | Crystalline Phase Fractions (mol%) | |||
---|---|---|---|---|
2M-Zirconolite | 4M-Zirconolite | Perovskite | ||
CaZrTi2O7 | x = 0 | 92.6 | - | 7.4 |
CaZr0.8Ce0.2Ti2O7 | x = 0.2 | 63.4 | 8.7 | 27.9 |
CaZr0.65Ce0.35Ti2O7 | x = 0.35 | 22.5 | 56.4 | 21.1 |
Ca0.8Ce0.2ZrTi1.6Al0.4O7 | y = 0.2 | 91.6 | - | 8.4 |
Ca0.65Ce0.35ZrTi1.3Al0.7O7 | y = 0.35 | 100 | - | - |
Composition | Phase | Zirconolite | Rwp | Rp | |||||
---|---|---|---|---|---|---|---|---|---|
a (Å) | b (Å) | c (Å) | β (°) | V (Å3) | |||||
CaZrTi2O7 | x = 0 | 2M | 12.4459(6) | 7.2701(4) | 11.3629(6) | 100.5782(18) | 1010.67(9) | 8.65 | 6.56 |
CaZr0.8Ce0.2Ti2O7 | x = 0.2 | 2M | 12.4861(16) | 7.2835(9) | 11.3991(15) | 100.578(4) | 1019.1(2) | 9.36 | 5.93 |
4M | 12.480(12) | 7.197(6) | 23.09(2) | 85.01(4) | 2066(3) | ||||
CaZr0.65Ce0.35Ti2O7 | x = 0.35 | 2M | 12.499(13) | 7.274(8) | 11.393(14) | 100.70(5) | 1018(2) | 7.74 | 5.71 |
4M | 12.469(8) | 7.206(5) | 23.066(13) | 84.62(3) | 2063(2) | ||||
Ca0.8Ce0.2ZrTi1.6Al0.4O7 | y = 0.2 | 2M | 12.4530(5) | 7.2520(3) | 11.3401(5) | 100.6899(19) | 1006.34(7) | 8.54 | 6.5 |
Ca0.65Ce0.35ZrTi1.3Al0.7O7 | y = 0.35 | 2M | 12.500(5) | 7.270(3) | 11.393(5) | 100.67(2) | 1017.5(7) | 10.43 | 7.77 |
Composition | Elemental Composition (mol%) | Ce/(Zr + Ce) | Ce/(Ca + Ce) | ||||
---|---|---|---|---|---|---|---|
Ca | Zr | Ce | Ti | Al | |||
CaZrTi2O7 | 24.7 | 25.7 | - | 49.6 | - | - | - |
CaZr0.8Ce0.2Ti2O7 | 25.3 | 20.0 | 5.6 | 49.1 | - | 0.22 | - |
CaZr0.65Ce0.35Ti2O7 | 24.2 | 16.6 | 9.8 | 49.4 | - | 0.37 | - |
Ca0.8Ce0.2ZrTi1.6Al0.4O7 | 19.6 | 27.0 | 4.7 | 40.0 | 8.7 | - | 0.19 |
Ca0.65Ce0.35ZrTi1.3Al0.7O7 | 16.4 | 24.6 | 9.7 | 35.3 | 14.0 | - | 0.37 |
Composition | Crystalline Phase Content (mol%) | |
---|---|---|
Zirconolite | Perovskite | |
CaZrTi2O7 | 83.4 (92.6) | 16.6 (7.4) |
CaZr0.8Ce0.2Ti2O7 | 69.0 (72.1) | 31.0 (27.9) |
CaZr0.65Ce0.35Ti2O7 | 37.4 (78.9) | 62.6 (21.1) |
Ca0.8Ce0.2ZrTi1.6Al0.4O7 | 70.3 (91.6) | 29.7 (8.4) |
Ca0.65Ce0.35ZrTi1.3Al0.7O7 | 66.0 (100) | 34.0 (0) |
Composition | Elemental Composition (mol%) | ||||
---|---|---|---|---|---|
Ca | Zr | Ce | Ti | Al | |
CaZr0.65Ce0.35Ti2O7 (No. 1, zirconolite) | 20.8 (24.2) | 26.3 (16.6) | 5.2 (9.8) | 47.7 (49.4) | - |
CaZr0.65Ce0.35Ti2O7 (No. 2, perovskite) | 29.3 (31.9) | 5.2 (5.7) | 14.1 (10.5) | 51.4 (51.9) | - |
Ca0.8Ce0.2ZrTi1.6Al0.4O7 (No. 3, zirconolite) | 16.3 (16.4) | 28.7 (24.6) | 7.8 (9.7) | 32.9 (35.3) | 14.2 (14.0) |
Ca0.8Ce0.2ZrTi1.6Al0.4O7 (No. 4, perovskite) | 30.0 (36.5) | 6.0 (6.6) | 12.6 (6.8) | 37.7 (38.7) | 13.7 (11.4) |
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Hayashizaki, K.; Hirooka, S.; Yamada, T.; Sunaoshi, T.; Murakami, T.; Saito, K. Reduction and Phase Transformation of Ce-Doped Zirconolites. Ceramics 2025, 8, 24. https://doi.org/10.3390/ceramics8010024
Hayashizaki K, Hirooka S, Yamada T, Sunaoshi T, Murakami T, Saito K. Reduction and Phase Transformation of Ce-Doped Zirconolites. Ceramics. 2025; 8(1):24. https://doi.org/10.3390/ceramics8010024
Chicago/Turabian StyleHayashizaki, Kohei, Shun Hirooka, Tadahisa Yamada, Takeo Sunaoshi, Tatsutoshi Murakami, and Kosuke Saito. 2025. "Reduction and Phase Transformation of Ce-Doped Zirconolites" Ceramics 8, no. 1: 24. https://doi.org/10.3390/ceramics8010024
APA StyleHayashizaki, K., Hirooka, S., Yamada, T., Sunaoshi, T., Murakami, T., & Saito, K. (2025). Reduction and Phase Transformation of Ce-Doped Zirconolites. Ceramics, 8(1), 24. https://doi.org/10.3390/ceramics8010024