The adsorption of a single Ti atom on single-wall silicon carbide nanotubes (SWSiCNTs) and the corresponding adsorption of hydrogen molecules to the Ti atom is investigated by using first-principles method. We present and discuss the most energetically favorable sites for a single Ti atom adsorbed on the outside of SWSiCNTs. Ti and C atoms form a strong chemical bond while the interaction between Ti and Si is rather weak. Up to four hydrogen molecules can be attached to the Ti atom and all of them are not dissociative. (c) 2007 Elsevier B.V. All rights reserved.