Rate-Limiting Step in Batteries with Metal Oxides as the Energy Materials
| Autor: | Mingchao Shang, Yong Zhang, Yan Wang, Qiang Wang, Yuan Yang |
|---|---|
| Rok vydání: | 2018 |
| Předmět: |
Materials science
020209 energy Oxide 02 engineering and technology Overpotential 021001 nanoscience & nanotechnology Electron spectroscopy Amorphous solid Crystal Metal chemistry.chemical_compound chemistry Chemical engineering visual_art Phase (matter) 0202 electrical engineering electronic engineering information engineering visual_art.visual_art_medium General Materials Science Cyclic voltammetry 0210 nano-technology |
| Zdroj: | ACS applied materialsinterfaces. 10(8) |
| ISSN: | 1944-8252 |
| Popis: | Metal oxides are used as the energy materials in some aqueous and nonaqueous batteries. However, a large overpotential and poor rate-performance limit their wide application. Low electrical conductivity of the oxide is commonly considered to be the reason for these limitations. The present study specifically reveals the electrochemical reduction process of α-Fe2O3 particles by using a cyclic voltammetry technique combined with an electron spectroscopy technique. SEM and TEM observe the phase and crystal structure transformation process during α-Fe2O3 reduction at the nanoscale, and EDS analyzes the composition change of particles at various periods. The surface of α-Fe2O3 particles is reduced to an amorphous compound first, and then O2– ions diffuse from the crystal matrix toward the outside simultaneously causing defects inside the particles. Experiments prove that γ-Fe2O3, Fe3O4, CuO, and Bi2O3 have the same rate-limiting step as α-Fe2O3; that is, O2– ions diffuse inside the oxide particles toward the o... |
| Databáze: | OpenAIRE |
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