Limitations of conversion factor approaches in the synthesis of complex oxide superconductors: a case study on Y123 and Y358
Öz
Accurate precursor calculation is essential for the successful synthesis of oxide-based superconductors. This study compares two commonly used methods stoichiometric balance and conversion factor (CF) approaches in the synthesis of YBa2Cu3O7-δ (Y123) and Y3Ba5Cu8O18+δ (Y358) superconductors. The analysis reveals that CF methods introduce substantial systematic errors, particularly for Y2O3, with deviations reaching 21.2% in Y123. These errors are exacerbated in Y358 due to its increased stoichiometric complexity. Unlike stoichiometric methods, CF approaches neglect volatile losses such as CO2 and fail to adjust for oxygen non-stoichiometry (δ variations), leading to misestimations in precursor masses. Statistical tests (χ2 < 0.001, RMSE) and experimental data confirm that these inaccuracies can negatively impact phase purity and crystallographic quality. A strong correlation (R2 = 0.847) between stoichiometric accuracy and phase formation quality emphasizes the importance of rigorous calculation. This study highlights the inherent limitations of CF-based shortcuts and underscores the necessity of comprehensive stoichiometric modeling, especially in complex oxide systems. The findings also provide an educational framework to address common misconceptions in materials synthesis, particularly for early-stage researchers in solid-state chemistry and materials science.
Anahtar Kelimeler
Conversion factors, Precursor optimization, Stoichiometric calculations, Synthesis accuracy YBCO superconductors
Destekleyen Kurum
This study was financially supported by the Scientific Research Projects Coordination Unit (GÜBAP) of Gümüşhane University under the project number 13.F5120.02.1.
Proje Numarası
13.F5120.02.1
Teşekkür
The author also extends sincere thanks to the editors and reviewers for their valuable evaluations and constructive feedback during the peer review process.
Kaynakça
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