Hydrothermal synthesis of Fe-doped ZnAl2O4 nanosheets: bandgap engineering and room temperature ferromagnetism

Autor: Bathula Babu, Thirumala Rao Gurugubelli, Jonghoon Kim, Kisoo Yoo
Rok vydání: 2021
Předmět:
Zdroj: Chemical Papers. 75:6407-6416
ISSN: 2585-7290
0366-6352
DOI: 10.1007/s11696-021-01807-4
Popis: In this study, well-separated Fe-doped ZnAl2O4 nanosheets were synthesized by a co-precipitation assisted hydrothermal method (220 °C). The as-synthesized nanosheets were characterized by X-ray diffraction, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV- diffuse reflectance spectroscopy and vibrating sample magnetometer studies. The diffraction patterns reveal that there is no noticeable effect of doped Fe ions on the crystal structure of ZnAl2O4. This also confirms the crystallinity and pure spinel structure formation. In addition, no characteristic diffraction peaks related to any impurity, cluster formation, or secondary phase of Fe were detected. The XPS spectra of Fe-doped ZnAl2O4 confirms the presence target elements such as Zn, Al, O, and Fe. It is also confirmed the existence of mixed oxidation states, i.e., Fe2+ and Fe3+, in the optimized sample ZAO-Fe-3 (i.e., 3% of Fe ions doped ZnAl2O4). TEM images of pure ZnAl2O4 show a micro-hexagonal structure, whereas the Fe-doped ZnAl2O4 exhibits nanosheet-like structure. DRS analysis confirms that Fe doping modifies the bandgap energy of ZnAl2O4 with increasing Fe content. The M–H hysteresis curves of Fe-doped ZnAl2O4 exhibited clear room temperature ferromagnetism.
Databáze: OpenAIRE
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