Abstract

Herein, the structural, electronic and energetic properties of Nb-doped NaAlH4 (001) from the surface to bulk have been studied by first principles calculations. Nb doping introduces charge transfer from Nb atom to Al atoms due to abundant electrons. On one hand, this will reduce the giving effect of electrons from H to Al atoms. On other hand, the original AlH4 groups are distorted by the strong interaction between Nb and Al atoms. These results facilitate the removal of H atoms from the Al atom. The dual effects of Nb doping are also analyzed in different layers. In the top and second layers, the covalent interaction between Nb and Al contributes to the formation of NbAl phase. In deeper layers, the strong interaction between Nb and H atoms reduces the electrons densities around Al, the shortage of electrons favors AlH2 unit attracts its around AlH4 unit to form the Al2H6 unit. The calculated ab initio molecular dynamics properties indicate that high temperature firstly improves the diffusion of Al atoms from Nb. The NbH2 phases may formed accompanied by the removal of Al atoms. Thus, the catalytic process of Nb in the dehydrogenation of NaAlH4 has been given.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.