Formation of Solid Solutions and Physicochemical Properties of the High-Entropy Ln1−xSrx(Co,Cr,Fe,Mn,Ni)O3−δ (Ln = La, Pr, Nd, Sm or Gd) Perovskites
Abstract
:1. Introduction
- long range antiferromagnetic (AFM) order is present despite the extreme ionic disorder and the high degree of dilution with non-magnetic ions;
- gradual magnetic transitions are spaced over a wide range of temperatures;
- short-range magnetic correlation is present well above Néel temperature (TN);
- Based on such characteristics it can be anticipated that the further development of perovskite-structured HEOx might result in obtaining of a number of potentially unique magnetic materials.
2. Materials and Methods
3. Results and Discussion
3.1. Crystal Structure of Ln(Co,Cr,Fe,Mn,Ni)O3−δ
3.2. Scanning Electron Microscopy Plus Energy-Dispersive X-ray Spectroscopy (SEM+EDS) Analysis of the Ln(Co,Cr,Fe,Mn,Ni)O3−δ Series
3.3. Thermomechanical Behavior of the Ln(Co,Cr,Fe,Mn,Ni)O3−δ Series
3.4. Electrical Conductivity of the Ln(Co,Cr,Fe,Mn,Ni)O3−δ Series
3.5. Strontium Solubility in Ln1−xSrx(Co,Cr,Fe,Mn,Ni)O3−δ Series
4. Conclusions
Supplementary Materials
Author Contributions
Funding
Conflicts of Interest
References
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As-Calcined Powders (Calcined at 700 °C for 6 h, Cooled Down with the Furnace) | |||||||||||
Phase | ρtheo (g/cm3) | a (Å) | b (Å) | c (Å) | V (Å3) | a0 (Å) | Rwp (%) | Gof | |||
La(Co,Cr,Fe,Mn,Ni)O3−δ | R-3c | 6.91 | 5.5086(2) | - | 13.371(1) | 58.563(6) | 3.8834(1) | 2.82 | 1.05 | - | - |
Pr(Co,Cr,Fe,Mn,Ni)O3−δ | Pbnm | 7.10 | 7.6965(3) | 5.4709(2) | 5.4411(2) | 57.277(4) | 3.8547(1) | 3.18 | 3.25 | 1.0053 | 0.9998 |
Nd(Co,Cr,Fe,Mn,Ni)O3−δ | Pbnm | 7.26 | 7.6703(4) | 5.4742(3) | 5.4090(3) | 56.779(6) | 3.8435(1) | 5.01 | 3.52 | 1.0093 | 0.9973 |
Sm(Co,Cr,Fe,Mn,Ni)O3−δ | Pbnm | 7.53 | 7.6169(4) | 5.5062(3) | 5.3525(3) | 56.121(5) | 3.8266(1) | 2.69 | 1.33 | 1.0223 | 0.9938 |
Gd(Co,Cr,Fe,Mn,Ni)O3−δ | Pbnm | 7.81 | 7.5724(3) | 5.5370(3) | 5.2068(3) | 55.522(4) | 3.8149(1) | 2.13 | 1.25 | 1.0341 | 0.9724 |
Sinters (sintered at 1000 °C for 20 h, cooled down by quenching) | |||||||||||
Phase | ρtheo (g/cm3) | a (Å) | b (Å) | c (Å) | V (Å3) | a0 (Å) | Rwp (%) | Gof | |||
La(Co,Cr,Fe,Mn,Ni)O3−δ | Pbnm | 6.92 | 7.7472(2) | 5.5116(1) | 5.4671(1) | 58.360(2) | 3.8789(1) | 7.17 | 2.01 | 1.0061 | 0.9980 |
Pr(Co,Cr,Fe,Mn,Ni)O3−δ | Pbnm | 7.10 | 7.6976(1) | 5.4673(1) | 5.4413(1) | 57.250(1) | 3.8541(1) | 3.77 | 5.52 | 1.0045 | 0.9997 |
Nd(Co,Cr,Fe,Mn,Ni)O3−δ | Pbnm | 7.26 | 7.6728(1) | 5.4751(1) | 5.4099(1) | 56.817(1) | 3.8444(1) | 4.06 | 2.60 | 1.0091 | 0.9971 |
Sm(Co,Cr,Fe,Mn,Ni) O3−δ | Pbnm | 7.54 | 7.6178(1) | 5.4987(1) | 5.3532(1) | 56.059(1) | 3.8272(1) | 3.05 | 1.96 | 1.0208 | 0.9938 |
Gd(Co,Cr,Fe,Mn,Ni) O3−δ | Pbnm | 7.82 | 7.5726(1) | 5.5293(1) | 5.2980(1) | 55.458(1) | 3.8135(1) | 2.53 | 1.89 | 1.0326 | 0.9894 |
Average Composition (at.%) | |||||||
Ln | Co | Cr | Fe | Mn | Ni | O | |
La(Co,Cr,Fe,Mn,Ni)O3−δ | 22.9 | 4.6 | 6.0 | 4.8 | 4.3 | 4.4 | 53 |
Pr(Co,Cr,Fe,Mn,Ni)O3−δ | 24.1 | 4.6 | 4.5 | 4.7 | 4.9 | 4.8 | 53 |
Nd(Co,Cr,Fe,Mn,Ni)O3−δ | 25.6 | 4.6 | 5.1 | 5.4 | 5.2 | 4.7 | 49 |
Sm(Co,Cr,Fe,Mn,Ni)O3−δ | 25.8 | 5.1 | 5.0 | 5.6 | 5.2 | 4.4 | 49 |
Gd(Co,Cr,Fe,Mn,Ni)O3−δ | 23.5 | 5.7 | 4.8 | 5.1 | 5.4 | 5.0 | 51 |
Cations’ ratios | |||||||
Ln | Co | Cr | Fe | Mn | Ni | O | |
La(Co,Cr,Fe,Mn,Ni)O3−δ | - | 0.191 | 0.249 | 0.199 | 0.178 | 0.182 | - |
Pr(Co,Cr,Fe,Mn,Ni)O3−δ | - | 0.196 | 0.191 | 0.200 | 0.209 | 0.204 | - |
Nd(Co,Cr,Fe,Mn,Ni)O3−δ | - | 0.184 | 0.204 | 0.216 | 0.208 | 0.188 | - |
Sm(Co,Cr,Fe,Mn,Ni)O3−δ | - | 0.202 | 0.198 | 0.221 | 0.206 | 0.174 | - |
Gd(Co,Cr,Fe,Mn,Ni)O3−δ | - | 0.219 | 0.185 | 0.196 | 0.208 | 0.192 | - |
Composition | TEC (10−6 K−1) ((Heating) Run) | TEC (10−6 K−1) ((Cooling) Run) |
---|---|---|
La(Co,Cr,Fe,Mn,Ni)O3−δ | 15.4(1) | 15.4(1) |
Pr(Co,Cr,Fe,Mn,Ni)O3−δ | 14.6(1) | 14.4(1) |
Nd(Co,Cr,Fe,Mn,Ni)O3−δ | 14.8(1) | 14.7(1) |
Sm(Co,Cr,Fe,Mn,Ni)O3−δ | 14.6(1) | 14.4(1) |
Gd(Co,Cr,Fe,Mn,Ni)O3−δ | 14.1(1) | 14.0(1) |
Composition | Ea (eV) | T (°C) | σmax (S·cm−1) |
---|---|---|---|
La(Co,Cr,Fe,Mn,Ni)O3−δ | 0.363(3) | 150–900 | 3.2 |
Pr(Co,Cr,Fe,Mn,Ni)O3−δ | 0.362(3) | 150–700 | 2.3 |
Nd(Co,Cr,Fe,Mn,Ni)O3−δ | 0.365(3) | 150–700 | 1.6 |
Sm(Co,Cr,Fe,Mn,Ni)O3−δ | 0.349(2) | 200–900 | 1.2 |
Gd(Co,Cr,Fe,Mn,Ni)O3−δ | 0.417(2) | 250–900 | 1.5 |
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Dąbrowa, J.; Zielińska, K.; Stępień, A.; Zajusz, M.; Nowakowska, M.; Moździerz, M.; Berent, K.; Szymczak, M.; Świerczek, K. Formation of Solid Solutions and Physicochemical Properties of the High-Entropy Ln1−xSrx(Co,Cr,Fe,Mn,Ni)O3−δ (Ln = La, Pr, Nd, Sm or Gd) Perovskites. Materials 2021, 14, 5264. https://doi.org/10.3390/ma14185264
Dąbrowa J, Zielińska K, Stępień A, Zajusz M, Nowakowska M, Moździerz M, Berent K, Szymczak M, Świerczek K. Formation of Solid Solutions and Physicochemical Properties of the High-Entropy Ln1−xSrx(Co,Cr,Fe,Mn,Ni)O3−δ (Ln = La, Pr, Nd, Sm or Gd) Perovskites. Materials. 2021; 14(18):5264. https://doi.org/10.3390/ma14185264
Chicago/Turabian StyleDąbrowa, Juliusz, Klaudia Zielińska, Anna Stępień, Marek Zajusz, Margarita Nowakowska, Maciej Moździerz, Katarzyna Berent, Maria Szymczak, and Konrad Świerczek. 2021. "Formation of Solid Solutions and Physicochemical Properties of the High-Entropy Ln1−xSrx(Co,Cr,Fe,Mn,Ni)O3−δ (Ln = La, Pr, Nd, Sm or Gd) Perovskites" Materials 14, no. 18: 5264. https://doi.org/10.3390/ma14185264