Meenakshi Arya, Mayuri N. Gandhi, Shriganesh S. Prabhu, Venu Gopal Achanta, Siddhartha P Duttagupta
{"title":"Nickel-cobalt-zinc ferrite nanoparticles for radio-frequency/terahertz frequency-selective surface application","authors":"Meenakshi Arya, Mayuri N. Gandhi, Shriganesh S. Prabhu, Venu Gopal Achanta, Siddhartha P Duttagupta","doi":"10.1049/nde2.12004","DOIUrl":null,"url":null,"abstract":"<p>Nanoparticles of Ni<sub>0.5</sub>Co<sub>0.2</sub>Zn<sub>0.3</sub>Fe<sub>2</sub>O<sub>4</sub> were prepared using the sol-gel combustion route. The nanoparticles were characterised by x-ray diffraction to confirm single-phase formation in a cubic spinel structure. Micro- and nanostructural analyses were carried out using field emission-scanning electron microscopy and field emission-transmission electron microscopy, respectively. A planetary ball milling technique was used to grind the powder into nanoparticles; the average particle size was 64 nm. Energy-dispersive X-ray spectroscopy was used to determine the atomic composition of the sample. Radio-frequency characteristics were recorded for dielectric measurement in a frequency range of 1 Hz to 15 MHz using a broadband dielectric spectrometer. Terahertz (THz) time-domain spectroscopy was performed to study THz-optical parameters such as refractive index, dielectric constant, and conductivity at room temperature in a frequency range of 0.3−2.2 THz using an indigenously developed THz time-domain spectroscopy setup. The magnetic properties of the sample were studied using a SQUID vibrating sample magnetometer under an applied magnetic field of ±10 kOe. An examination of M-H loops revealed that the saturation magnetization <math>\n <mrow>\n <mo>(</mo>\n <msub>\n <mi>M</mi>\n <mi>s</mi>\n </msub>\n <mo>)</mo>\n </mrow></math>, remanent magnetization <math>\n <mrow>\n <mo>(</mo>\n <msub>\n <mi>M</mi>\n <mi>r</mi>\n </msub>\n <mo>)</mo>\n </mrow></math> and coercivity <math>\n <mrow>\n <mo>(</mo>\n <msub>\n <mi>H</mi>\n <mi>c</mi>\n </msub>\n <mo>)</mo>\n </mrow></math> increased with an increase in temperature from 300 to 50 K.</p>","PeriodicalId":36855,"journal":{"name":"IET Nanodielectrics","volume":null,"pages":null},"PeriodicalIF":3.8000,"publicationDate":"2021-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ietresearch.onlinelibrary.wiley.com/doi/epdf/10.1049/nde2.12004","citationCount":"4","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"IET Nanodielectrics","FirstCategoryId":"1085","ListUrlMain":"https://onlinelibrary.wiley.com/doi/10.1049/nde2.12004","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, ELECTRICAL & ELECTRONIC","Score":null,"Total":0}
引用次数: 4
Abstract
Nanoparticles of Ni0.5Co0.2Zn0.3Fe2O4 were prepared using the sol-gel combustion route. The nanoparticles were characterised by x-ray diffraction to confirm single-phase formation in a cubic spinel structure. Micro- and nanostructural analyses were carried out using field emission-scanning electron microscopy and field emission-transmission electron microscopy, respectively. A planetary ball milling technique was used to grind the powder into nanoparticles; the average particle size was 64 nm. Energy-dispersive X-ray spectroscopy was used to determine the atomic composition of the sample. Radio-frequency characteristics were recorded for dielectric measurement in a frequency range of 1 Hz to 15 MHz using a broadband dielectric spectrometer. Terahertz (THz) time-domain spectroscopy was performed to study THz-optical parameters such as refractive index, dielectric constant, and conductivity at room temperature in a frequency range of 0.3−2.2 THz using an indigenously developed THz time-domain spectroscopy setup. The magnetic properties of the sample were studied using a SQUID vibrating sample magnetometer under an applied magnetic field of ±10 kOe. An examination of M-H loops revealed that the saturation magnetization , remanent magnetization and coercivity increased with an increase in temperature from 300 to 50 K.