Catalytic mechanism of TiO2 quantum dots on the de/re-hydrogenation characteristics of magnesium hydride
| Autor: | Thakur Prasad Yadav, Uday Deshpandey, Sunita K. Pandey, Ashish Bhatnagar, Vivek Shukla, Rashmi Kesarwani |
|---|---|
| Rok vydání: | 2021 |
| Předmět: |
Materials science
Hydrogen Renewable Energy Sustainability and the Environment Kinetics Magnesium hydride Inorganic chemistry Energy Engineering and Power Technology chemistry.chemical_element Sorption Condensed Matter Physics Catalysis chemistry.chemical_compound Fuel Technology X-ray photoelectron spectroscopy chemistry Quantum dot Desorption |
| Zdroj: | International Journal of Hydrogen Energy. 46:37340-37350 |
| ISSN: | 0360-3199 |
| DOI: | 10.1016/j.ijhydene.2021.09.006 |
| Popis: | In the present study, the catalyst anatase titanium dioxide (TiO2) quantum dots (QDs) of size ∼ (2.50–4.00)nm was successfully synthesized by the hydrothermal method. The formation of TiO2: QDs has been established by UV–Vis spectroscopy and confirmed by transmission electron microscopy. Here, we report the catalytic action of TiO2:QDs on de/re-hydrogenation properties of magnesium hydride (MgH2/Mg). By catalyzing MgH2 through this catalyst, the onset desorption temperature of MgH2 gets reduced significantly from ∼360 °C (for ball-milled MgH2) to ∼260 °C. Moreover, the Mg-TiO2: QDs sample absorbed a significant amount of hydrogen up to ∼6.10 wt% in just 77sec at 280 °C. Improved rehydrogenation kinetics has been found even at lower temperatures by absorbing ∼5.30 wt% in 74 s at 225 °C and ∼5.0 wt% of hydrogen in 30 min at 100 °C. Based on structural,.microstructural, and XPS investigations, a feasible mechanism for improved hydrogen sorption and cyclic stability in MgH2 catalyzed with TiO2:QDs has been explained and discussed. To our knowledge, no studies have been carried out on the sorption of hydrogen in MgH2 catalyzed by TiO2:QDs. |
| Databáze: | OpenAIRE |
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