Studies in molybdenum/manganese content in the dual body-centered-cubic phases metal hydride alloys
| Autor: | Xingqun Liao, Kwo Young, Jean Nei, Zhoulan Yin |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
Materials science
Passivation Renewable Energy Sustainability and the Environment Hydride 05 social sciences Alloy Inorganic chemistry Analytical chemistry Energy Engineering and Power Technology chemistry.chemical_element 02 engineering and technology Electrolyte engineering.material 021001 nanoscience & nanotechnology Condensed Matter Physics Hydrogen storage Fuel Technology Lattice constant chemistry Molybdenum Phase (matter) 0502 economics and business engineering 050207 economics 0210 nano-technology |
| Zdroj: | International Journal of Hydrogen Energy. 41:15277-15286 |
| ISSN: | 0360-3199 |
| Popis: | A series of TiVCrMn-based body-centered-cubic (BCC) alloys with design compositions of Ti40V30Cr15Mn15−xMox, where x = 0, 2, 4, 6, 8, 10, and 12, were prepared by an arc melter. Their microstructures were characterized and compared to the hydrogen storage properties in both gaseous phase and electrochemistry. X-ray diffraction results indicate the alloys are dominated by either one (x = 0 and 2) or two BCC phases (x = 4 to 12). As the Mo-content in the alloy increases, much of the first BCC phase is replaced by the second BCC phase with a stronger metal–hydrogen bond, lattice constant of the first BCC phase increases while that of the second BCC phase remains about the same, and both gaseous and electrochemical hydrogen storage capacities and plateau pressure increases and then decreases. The boundary between the two BCC phases is found to be crucial for the hydrogen storage properties. Alloy with a composition of Ti40V30Cr15Mn11Mo4 shows a good balance among various electrochemical properties, and alloys with higher Mo-contents (8 at% for example) achieved discharge capacity up to 639 mAh g−1 at 4 mA g−1 but are less stable in 30% KOH due to cracking and surface oxidation. Using higher concentration of KOH at 50% as the electrolyte is able to improve 8 at% Mo-containing alloy by nearly 60% by reducing the adverse effect from passivation. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|
Full Text from ScienceDirect