Correlation between structural modifications and levitation performance in PAni-addition MgB2 bulk superconductors
Öz
In this study, bulk MgB2 superconductors with varying polyaniline (PAni) contents (0–6 wt%) were synthesized via a closed-tube method and heat-treated at 850 °C under Ar atmosphere. Structural characterization by X-ray diffraction revealed that increasing PAni content led to systematic decreases in lattice parameters (a, c), interplanar spacing d (101), and unit cell volume, attributed to partial carbon substitution from PAni decomposition. This substitution, due to the smaller atomic radius of carbon compared to boron, modifies the crystal lattice and influences electronic structure. Crystallite size, dislocation density, and lattice strain calculations indicated that low-to-moderate PAni additions increase defect density and microstrain, potentially enhancing flux pinning. SEM analysis showed notable microstructural changes, including reduced porosity and improved homogeneity at lower adding, while higher contents promoted grain growth. Magnetic levitation force measurements under field-cooled (FC) and zero-field-cooled (ZFC) conditions showed that optimal PAni additions (4.5–6 wt%) improved the maximum levitation force in FC mode, while higher adding levels caused a decline in the initial force in ZFC mode, as observed at both 20 K and 25 K. The results establish a direct link between lattice parameter modification and levitation performance, offering insights for tailoring MgB2-based superconductors for magnetic levitation applications.
Anahtar Kelimeler
Lattice parameter, Magnetic levitation force, MgB2 bulk superconductor, Polyaniline addition
Teşekkür
Yazar, malzeme tedarikindeki desteklerinden dolayı Prof. Dr. Burcu Savaşkan ve Dr. Vildan Erduran'a, üretim sürecine ve levitasyon ölçümlerine katkılarından dolayı Doç. Dr. Sait Barış Güner'e ve levitasyon sisteminin imalatından dolayı Prof. Dr. Şükrü Özçelik'e içten teşekkürlerini sunar.
Kaynakça
- Aquí-Romero, F., Willars-Rodríguez, F. J., Chávez-Urbiola, I. R., & Ramírez-Bon, R. (2020). ZnO2 films by successive ionic layer adsorption and reaction method and their conversion to ZnO ones for p-Si/n-ZnO photodiode applications. Semiconductor Science and Technology, 35(2). https://doi.org/10.1088/1361-6641/ab5f2a
- Aydın Ünal, F. (2024). Nadir toprak elementi (Gd) katkılı ZnO nanoparçacıkların sol-jel yöntemi ile sentezlenmesi ve karakteristik özelliklerinin incelenmesi. Afyon Kocatepe University Journal of Sciences and Engineering, 24(2), 424–433. https://doi.org/10.35414/akufemubid.1371091
- Bayazit, T., Kanmaz, İ., Tomakin, M., & Üzüm, A. (2025). Triple layer TiO2/HfO2/SiO2 thin film design for reduction of optical losses. Physica Scripta, 100(4). https://doi.org/10.1088/1402-4896/adc049
- Braccini, V., Nardelli, D., Penco, R., & Grasso, G. (2007). Development of ex situ processed MgB2 wires and their applications to magnets. In Physica C: Superconductivity and its Applications (Vol. 456, Issues 1–2, pp. 209–217). https://doi.org/10.1016/j.physc.2007.01.030
- Celik, S. (2016). Design of magnetic levitation force measurement system at any low temperatures from 20K to room temperature. Journal of Alloys and Compounds, 662, 546–556. https://doi.org/10.1016/j.jallcom.2015.11.230
- Cheng, C., Reddy, K. M., Hirata, A., Fujita, T., & Chen, M. (2017). Structure and mechanical properties of boron-rich boron carbides. Journal of the European Ceramic Society, 37(15), 4514–4523. https://doi.org/10.1016/j.jeurceramsoc.2017.06.017
- Deyu, G. K., Wenskat, M., Díaz-Palacio, I. G., Blick, R. H., Zierold, R., & Hillert, W. (2025). Recent advances in atomic layer deposition of superconducting thin films: a review. In Materials Horizons. Royal Society of Chemistry, 12, 5594-5626. https://doi.org/10.1039/d5mh00323g
- Duz, I., Guner, S. B., Erdem, O., Demir, I., Kapucu, V., Çelik, Ş., Ozturk, K. Hossain, S., Gencer, A., & Yanmaz, E. (2014). Comparison of levitation forces of bulk MgB2 superconductors produced by nano boron and carbon-doped nano boron. Journal of Superconductivity and Novel Magnetism, 27(10), 2241-2247. https://doi.org/10.1007/s10948-014-2602-4
- Erdem, O., Guner, S. B., Celik, S., & Kucukomeroglu, T. (2020). Superconducting and levitation force characterisation of pyrene added MgB2 bulk superconductors. Cryogenics, 112. https://doi.org/10.1016/j.cryogenics.2020.103205
- Güner, S. B. (2020). Effects of silver doping on magnetic levitation performance of MgB2 superconductors. Cryogenics, 108. https://doi.org/10.1016/j.cryogenics.2020.103061