Here, Zn ferrite is synthesized along with reduced graphene oxide (rGO) by a facile one-step hydrothermal method. The difference between the synthesized nanocomposites with those in other reported work is that the reaction conditions in this work are 160 oC for 12 h. The synthesized products are characterized by field-emission scanning electron microscopy, X-ray diffraction, Raman spectroscopy, X-ray photoelectron spectroscopy, and attenuated total reflection. Further, the adsorption property of rGO–Zn ferrite (rGZF) nanocomposite is studied after confirming its successful synthesis. The adsorption capacity of rGZFs toward rhodamine B (RB) is ˃ 9.3 mg/g, whereas that of bare ZF nanoparticles is 1.8 mg/g in aqueous media. The efficiencies of rGZF and bare ZF to remove RB are 99 % and 20 %, respectively. Employing rGZF, 60 % of RB is decomposed within 5 min. The kinetic study reveals that the adsorption process of removing RB by bare Zn ferrite follows pseudo-firstorder kinetics. However, after zinc ferrite is incorporated with rGO, the kinetics changes to pseudo-second-order. Furthermore, the Langmuir isotherm is accomplished by the adsorption process employing rGZF, indicating that a monolayer adsorption process occurs. The thermodynamic parameters of the process are also calculated.

Mechanochemical synthesis of zinc ferrite, ZnFe2O4, was attempted from a powder mixture of iron (III) oxide, alpha-Fe2O3 and zinc (II) oxide, ZnO. Nanocrystalline zinc ferrite, ZnFe2O4 powders were successfully synthesized only bymilling for 30 hours. Evidence of the ZnFe2O4 formation was absent for the powders milled for 10 and 20 hours; the milling lowered the crystallinity of the starting materials. Heating after milling enhanced the formation of ZnFe2O4, crystal growth of ZnFe2O4 and the unreacted starting materials. The unreacted starting materials decreased their amounts by heating at higher temperatures.

52mol% Fe2O3, 26mol% MnO의 조성에서 calcium과 vanadium의 동시첨가에 의한 투자율의 변화원인을 살펴보았다. 초투자율은 첨가물의 농도가 커짐에 따라 감사하였으나 소결체의 밀도나 입자크기는 증가하였으므로 초투자율의 변화는 미세구조의 변화로는 설명되지 않았다. 전기비저항은 첨가물의 농도가 증가함에 따라 증가하였으며 이는 입계의 고저항층의 생성과 vanadium ion에 의한 Fe2+이온의 산화로 설명되었다. 첨가물의 농도가 증가함에 따라, 초투자율의 제 2차 최대치가 나타나지 않는 것과 초투자율이 감소하는 것으로부터, 결정자기이방성 상수의 값은 음으로 커짐을 알 수 있었다. 투자육의 온도의존성과 비저항의 변화로부터, 첨가물의 농도에 따른 상온 초투자율의 감소는 Fe2+ 이온 농도의 감소에 따른 결정자기이방성 상수의 증가에 의한 효과와 입계에 유리질이 생겨 자벽이 쉽게 이동하지 못하는 효과 때문인 것으로 판단되었다.