Ultrahigh hydrogen-sorbing palladium metallic-glass nanostructures
[ X ]
Tarih
2019
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Royal Society of Chemistry
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
Pd-Based amorphous alloys can be used for hydrogen energy-related applications owing to their excellent sorption capacities. In this study, the sorption behaviour of dc magnetron-sputtered and chronoamperometrically-saturated Pd-Si-Cu metallic-glass (MG) nanofilms is investigated by means of aberration-corrected high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy, and electrochemical techniques. The volume expansion of ?V = 10.09 Å3 of a palladium hydride unit cell obtained from HRTEM images due to the hydrogenation of the Pd-MG nanofilms is 1.65 times larger than ?V of the Pd-polycrystalline counterpart loaded under the same conditions. Determined by scanning transmission electron microscopy-high annular dark-field imaging and electron energy loss spectroscopy, the huge difference between the two Pd-based systems is accounted for by the "nanobubbles" originating from hydrogenation, which generate active sites for the formation and expansion of spatially dispersed palladium hydride nanocrystals. A remarkable difference in the hydrogen sorption capacity is measured by electrochemical impedance spectroscopy compared to the Pd polycrystal nanofilms particularly in the ? and ? regions, where the maximum hydrogen to palladium ratio obtained from a combination of chronoamperometry and cyclic voltammetry is 1.56 and 0.61 for the MG and Pd-polycrystal nanofilms, respectively. The findings place Pd-MGs among suitable material candidates for future energy systems. © The Royal Society of Chemistry.
Açıklama
Anahtar Kelimeler
Amorphous alloys, Chronoamperometry, Cyclic voltammetry, Electrochemical impedance spectroscopy, Electron energy levels, Electron energy loss spectroscopy, Electron scattering, Energy dissipation, Expansion, Glass, High resolution transmission electron microscopy, Hydrides, Hydrogenation, Metallic glass, Palladium alloys, Polycrystals, Scanning electron microscopy, Sorption, X ray photoelectron spectroscopy, Aberration-corrected, Annular dark-field imaging, Electrochemical techniques, Hydrogen sorption capacity, Material candidate, Palladium hydride, Scanning transmission electron microscopy, Sorption capacities, Palladium compounds
Kaynak
Materials Horizons
WoS Q Değeri
Scopus Q Değeri
Q1
Cilt
6
Sayı
7
