Effect of Titanium Doping of Al(111) Surfaces on Alane Formation Mobility, and Desorption

Journal Article · Tue Jul 05 04:00:00 EDT 2011 · The Journal of Physical Chemistry C

DOI:https://doi.org/10.1021/jp203842r· OSTI ID:1049216

S, Chopra I; Graetz, J; Chaudhuri, S; Veyan, J -F; Chabal, Y J

Alanes are critical intermediates in hydrogen storage reactions for mass transport during the formation of complex metal hydrides. Titanium has been shown to promote hydrogen desorption and hydrogenation, but its role as a catalyst is not clear. Combining surface infrared (IR) spectroscopy and density functional theory (DFT), the role of Ti is explored during the interaction of atomic hydrogen with Ti-doped Al(111) surfaces. Titanium is found to reduce the formation of large alanes, due to a decrease of hydrogen mobility and to trapping of small alanes on Ti sites, thus hindering oligomerization. For high doping levels ({approx}0.27 ML Ti) on Al(111), only chemisorbed AlH{sub 3} is observed on Ti sites, with no evidence for large alanes. Titanium also dramatically lowers the desorption temperature of large alanes from 290 to 190 K, due to a more restricted translational motion of these alanes.

• Research Organization: BROOKHAVEN NATIONAL LABORATORY (BNL)
• Sponsoring Organization: USDOE SC OFFICE OF SCIENCE (SC)
• DOE Contract Number: AC02-98CH10886
• OSTI ID: 1049216
• Report Number(s): BNL--96483-2011-JA; KC0207010
• Journal Information: The Journal of Physical Chemistry C, Journal Name: The Journal of Physical Chemistry C Journal Issue: 33 Vol. 115; ISSN 1932-7447
• Country of Publication: United States
• Language: English

Related Subjects

08 HYDROGEN
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
CATALYSTS
DESORPTION
FUNCTIONALS
HYDRIDES
HYDROGEN
HYDROGEN STORAGE
HYDROGENATION
SPECTROSCOPY
TITANIUM
TRANSPORT
TRAPPING