# Magnetic Properties of NiZn Ferrite Nanofibers Prepared by Electrospinning
## 4 Conclusions  
Ni\({}_{0.5}\)Zn\({}_{0.5}\)Fe\({}_{2}\)O\({}_{4}\) ferrite nanofibers were fabricated by electrospinningning with a precursor solution of PVP, DMF, metal nitrate, and heat treatment. Since the nanofibers have a smaller specific surface area than the 0-dimensional nanoparticles, we confirmed that the diameter could not be a major factor of M\({}_{\text{s}}\) value when the difference of the samples was not large. Rather, a large amount of polymer added for the diameter control decreased the crystallite size during the calcination process and caused an unexpected change in the M\({}_{\text{s}}\) value. On the other hand, we confirmed that, when the diameter difference is not significant, the crystallite size can be a factor leading to the M\({}_{\text{s}}\) value tendency. The ability to tune the constants related to magnetic forces when making a film for electromagnetic interference shielding with a magnetic ceramic filler means that additional channels are available for optimizing the shielding efficiency and the frequency band. Moreover, the change of the crystallite size, according to the polymer content, provides a clue to controlling the magnetization behavior more economically than the conventional method with the heat treatment temperature control. It is possible to obtain the maximum shielding effect at the same cost by applying a combination of research themes of the size-dependent magnetic characteristics, development of a ferrite composition with excellent magnetic characteristics, and study of thickness to maximize impedance matching.  
Conceptualization, K.-H.N. and W.-Y.C. Methodology, K.-H.N. Validation, K.-H.N. and W.-T.K. Formal analysis, K.-H.N. Investigation, K.-H.N. and W.-T.K. Resources, T.-H.S. and W.-Y.C. Data curation, K.-H.N. Writing--original draft preparation, K.-H.N. Writing--review and editing, W.-Y.C. Visualization, K.-H.N. and W.-T.K. Supervision, W.-Y.C. Project administration, T.-H.S. and W.-Y.C. Funding acquisition, T.-H.S. and W.-Y.C. Funding: The Korea Agency for Infrastructure Technology Advancement under Construction Technology R&D project (Grant No. 18 SCIP-B146646-01) and National Research Foundation of Korea (Grant No. 2019R1I1A3A01057765) supported this work.  
The authors thank the researchers ([PERSON]) of the Korea Institute of Civil Engineering and Building Technology, for their time and contributions to the study.  
The authors declare no conflict of interest.  
\begin{table}
\begin{tabular}{c c c c} \hline \hline \multirow{2}{*}{**Samples**} & **Saturation Magnetization** & \multirow{2}{*}{**Coercivity (Oe)**} & **Remnant Magnetization** \\  & **(emu/g)** & & **(emu/g)** \\ \hline Sample A & 56.65 & 153.12 & 9.82 \\ Sample B & 48.09 & 150.41 & 7.37 \\ Sample C & 48.29 & 169.45 & 9.32 \\ NiZn ferrite Nanofibers & 37–90.2 & 43–175.3 & - \\
[8, 46, 47] & 23.95–56 & 16–200 & - \\ Nanoparticles [48, 49] & & & \\ \hline \hline \end{tabular}
\end{table}
Table 5: Saturation magnetization, coercivity, and remnant magnetization of Ni\({}_{0.5}\)Zn\({}_{0.5}\)Fe\({}_{2}\)O\({}_{4}\) nanofibers measured from samples A, B, and C.