A new approach to improve the electrochemical performance of ZnMn2O4 through a charge compensation mechanism using the substitution of Al3+ for Zn2+
| Autor: | Xianyu Zhu, Decheng Li, Jichun Huang, Zheng Ma, Chongxing Ji, Decheng Zhu, Jingbin Quan, Yixin Chen |
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| Rok vydání: | 2018 |
| Předmět: |
Valence (chemistry)
Materials science Annealing (metallurgy) General Chemical Engineering Doping chemistry.chemical_element 02 engineering and technology General Chemistry Manganese 010402 general chemistry 021001 nanoscience & nanotechnology Electrochemistry 01 natural sciences 0104 chemical sciences X-ray photoelectron spectroscopy chemistry Chemical engineering Spray drying 0210 nano-technology Faraday efficiency |
| Zdroj: | RSC Advances. 8:7361-7368 |
| ISSN: | 2046-2069 |
| DOI: | 10.1039/c8ra00310f |
| Popis: | ZnMn2O4 and Zn1−xAlxMn2O4 were synthesized by a spray drying process followed by an annealing treatment. Their structural and electrochemical characteristics were investigated by SEM, XRD, XPS, charge–discharge tests and EIS. XPS data indicate that the substitution of Al3+ for Zn2+ causes manganese to be in a mixed valence state by a charge compensation mechanism. Moreover, the presence of this charge compensation significantly improves the electrochemical performance of Zn1−xAlxMn2O4, such as increasing the initial coulombic efficiency, stabilizing the cycleability as well as improving the rate capability. The sample with 2% Al doping shows the best performance, with a first cycle coulombic efficiency of 69.6% and a reversible capacity of 597.7 mA h g−1 after 100 cycles. Even at the high current density of 1600 mA g−1, it still retained a capacity of 558 mA h g−1. |
| Databáze: | OpenAIRE |
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