Effects of Nickel and Magnesium on electrochemical performances of partial substitution in spinel ferrite
| Autor: | Unchista Wongpratat, Ekaphan Swatsitang, Pannawit Tipsawat, Santi Maensiri, Jessada Khajonrit |
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| Rok vydání: | 2020 |
| Předmět: |
Materials science
Mechanical Engineering Inorganic chemistry Spinel Metals and Alloys chemistry.chemical_element 02 engineering and technology Electrolyte engineering.material 010402 general chemistry 021001 nanoscience & nanotechnology Electrochemistry 01 natural sciences Redox 0104 chemical sciences Nickel chemistry Transition metal Mechanics of Materials Specific surface area Electrode Materials Chemistry engineering 0210 nano-technology |
| Zdroj: | Journal of Alloys and Compounds. 831:154718 |
| ISSN: | 0925-8388 |
| DOI: | 10.1016/j.jallcom.2020.154718 |
| Popis: | This work presents a synthesis of mixed transition metal spinel ferrite nanoparticles (Ni1-xMgxFe2O4) where x = 0, 0.25, 0.5, 0.75, and 1.00 by a hydrothermal route in an aloe vera extract solution. The prepared nanoparticles revealed a mesopore size with specific surface area between 57.11 and 145.16 m2/g. An analysis of the lattice parameter, chemical composition and oxidation state confirm that Ni2+ and Mg2+ ions were successfully partially substituted in spinel ferrite. The electrochemical measurement of Ni1-xMgxFe2O4 nanoparticles was performed in 6 M of KOH electrolyte. The most outstanding performance of the electrodes was noticed in the MgFe2O4and Ni0·25Mg0·75Fe2O4 electrodes with specific capacitance of 259.89 F/g and 133.95 F/g at 0.5 A/g current density, respectively. These high specific capacitances are due to the high ratio of Fe ions in the spinel structure. Another significant improvement was in electrode stability which strongly depends on the ratio of (Ni, Mg) to Fe ions since the efficiency of a fast redox reaction of Fe ions declines with longer usage cycles due to the irreversible redox reaction. After testing 1000 cycles, the specific capacitance of MgFe2O4 was maintained at 71.76% while Ni0·25Mg0·75Fe2O4 was as high as 88.79%. Meanwhile, the most durable electrode was the Ni0·75Mg0·25Fe2O4 electrode of which the specific capacitance gradually increased from its initial value by 4.25% in terms of the highest ratio of Ni and Mg per Fe. |
| Databáze: | OpenAIRE |
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