@Article{CL.2025.223.261,
AUTHOR = {U. Anwar, N. A. Noor, S. Mumtaz, I. M. Moussad},
TITLE = {Impedance spectroscopy insights into (NiO)(<sub>0.5</sub>)/(Fe<sub>2</sub>O<sub>3</sub>)(<sub>0.5</sub>)@C@MoS<sub>2</sub> nanofibers composite for tunable EMI shielding applications},
JOURNAL = {Chalcogenide Letters},
VOLUME = {22},
YEAR = {2025},
NUMBER = {3},
PAGES = {261--276},
URL = {http://www.techscience.com/CL/v22n3/64905},
ISSN = {1584-8663},
ABSTRACT = {The combination of two-step synthesis processes is employed for the fabrication of 
(NiO)(<sub>0.5</sub>)/(Fe<sub>2</sub>O<sub>3</sub>)(<sub>0.5</sub>)@C@MoS<sub>2</sub> (NFCM) nanofibers composite through electrospinning 
and hydrothermal techniques. This nanofiber composite is designed for tunable dielectric 
materials and electromagnetic interference (EMI) shielding applications. Using impedance 
spectroscopy, the electrical properties of an NFCM pellet are analyzed using an equivalent 
circuit model (R<sub>1</sub><Q<sub>1</sub><), with a primary focus on the variation of relaxation time with frequency 
at different temperatures. Utilizing the Mott. variable range hopping (MVRH) model, and 
small polaronic hopping model, the localization length of the hoping carriers is determined 
to be 0.98 Å and the activation energy of thermally activated charge carriers is determined 
to be (E<sub>a</sub>=.0.27eV). The activation energy calculated from the impedance, SPH model, and 
conductivity plot are inaudibly comparable representing the conduction and relaxation 
process associated with the same electroactive regions. The (NFCM nanofibers composite 
exhibits higher conductivity at all temperature ranges, which is a crucial attribute for 
effective EMI shielding applications. In the X-band frequency range (8.2–12.4 GHz), 
the calculated EMI shielding effectiveness of NFCM nanofibers composite is 24.25 dB, this 
qualifies them for use in high frequency applications. },
DOI = {10.15251/CL.2025.223.261}
}