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Excellent catalysis of Mn(3)O(4) nanoparticles on the hydrogen storage properties of MgH(2): an experimental and theoretical study
Recently, transition metal oxides have been evidenced to be superior catalysts for improving the hydrogen desorption/absorption performance of MgH(2). In this paper, Mn(3)O(4) nanoparticles with a uniform size of around 10 nm were synthesized by a facile chemical method and then introduced to modify...
Autores principales: | , , , , , , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
RSC
2020
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9418404/ https://www.ncbi.nlm.nih.gov/pubmed/36132300 http://dx.doi.org/10.1039/d0na00137f |
Sumario: | Recently, transition metal oxides have been evidenced to be superior catalysts for improving the hydrogen desorption/absorption performance of MgH(2). In this paper, Mn(3)O(4) nanoparticles with a uniform size of around 10 nm were synthesized by a facile chemical method and then introduced to modify the hydrogen storage properties of MgH(2). With the addition of 10 wt% Mn(3)O(4) nanoparticles, the MgH(2)–Mn(3)O(4) composite started to release hydrogen at 200 °C and approximately 6.8 wt% H(2) could be released within 8 min at 300 °C. For absorption, the completely dehydrogenated sample took up 5.0 wt% H(2) within 10 min under 3 MPa hydrogen even at 100 °C. Compared with pristine MgH(2), the activation energy value of absorption for the MgH(2) + 10 wt% Mn(3)O(4) composite decreased from 72.5 ± 2.7 to 34.4 ± 0.9 kJ mol(−1). The catalytic mechanism of Mn(3)O(4) was also explored and discussed with solid evidence from X-ray diffraction (XRD), Transmission Electron Microscope (TEM) and Energy Dispersive X-ray Spectroscopy (EDS) studies. Density functional theory calculations revealed that the Mg–H bonds were elongated and weakened with the doping of Mn(3)O(4). In addition, a cycling test showed that the hydrogen storage capacity and reaction kinetics of MgH(2)–Mn(3)O(4) could be favourably preserved in 20 cycles, indicative of promising applications as a solid-state hydrogen storage material in a future hydrogen society. |
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