Show/Hide Menu
Hide/Show Apps
anonymousUser
Logout
Türkçe
Türkçe
Search
Search
Login
Login
OpenMETU
OpenMETU
About
About
Açık Bilim Politikası
Açık Bilim Politikası
Frequently Asked Questions
Frequently Asked Questions
Browse
Browse
By Issue Date
By Issue Date
Authors
Authors
Titles
Titles
Subjects
Subjects
Communities & Collections
Communities & Collections
Temel prensipler yöntemiyle magnezyum ve demir - titanyum hidrürlerinin modellenmesi, tasarımı ve üretimi
Download
T0RJNU1EQT0.pdf
Date
2008
Author
Aydınol, Kadri M.
Tan, Serdar
Akyıldız, Hasan
Kınacı, Alper
Şen, Fatih
Metadata
Show full item record
This work is licensed under a
Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License
.
Item Usage Stats
0
views
0
downloads
A candidate hydrogen storing material should have high storage capacity and fast dehydrogenation kinetics. On this basis, magnesium hydride (MgH2) is an outstanding compound with 7.66 wt % storage capacity, despite its slow dehydriding kinetics and high desorption temperature. Therefore in this study, bulk and surface alloys of Mg with improved hydrogen desorption characteristics were investigated. In this respect, formation energies of alloyed bulk MgH2 as well as the adsorption energies on alloyed magnesium (Mg) and MgH2 surface structures were calculated by total energy pseudopotential methods. Furthermore, the effect of substitutionally placed dopants on the dissociation of hydrogen molecule (H2) at the surface of Mg was studied via Molecular Dynamics (MD). The results displayed that 31 out of 32 selected dopants contributed to the decrease in formation energy of MgH2 within a range of ~ 37 kJ/mol-H2 where only Sr did not exhibit any such effect. The most favorable elements in this respect came out to be; P, K, Tl, Si, Sn, Ag, Pb, Au, Na, Mo, Ge and In. Afterwards, a systematical study within adsorption characteristics of hydrogen on alloyed Mg surfaces (via dynamic calculations) as well as calculations regarding adsorption energies of the impurity elements were performed. Accordingly, Mo and Ni yielded lower adsorption energies; -9.2626 and -5.2995 eV for substitutionally alloyed surfaces, respectively. MD simulations presented that Co is found to have a splitting effect on H2 in 50 fs, where the first hydrogen atom is immediately adsorbed on Mg substrate. Finally, charge density distributions were realized to verify the distinguished effects of most 3d and 4d transition metals in terms of their catalyzer effects. 7 In experimental studies, the FeTi compound was produced by the electrodeoxidation method. In addition, the catalyzer effect of Co in the hdriding of magnesium was investigated in thin film form.
Subject Keywords
Magnesium Hydride
,
Hydrogen Storage
,
First Principles
,
Molecular Dynamics
,
Surface Adsorption
URI
https://app.trdizin.gov.tr/publication/project/detail/T0RJNU1EQT0
https://hdl.handle.net/11511/49931
Collections
Department of Metallurgical and Materials Engineering, Project and Design