Abstract
Presented are thermal desorption spectroscopy (TDS) measurements of
iso-/
n-butane adsorption on a variety of TiO
2 nanotubes (TiNTs) samples which are characterized by different crystal structures. The results are compared with a prior study on anatase(0
0
1) thin films grown on SrTiO
3(0
0
1). A distinct kinetic structure–activity relationship was present, i.e., the binding energies of the alkanes depend on the polymorph (anatase vs. mixed anatase/rutile) of TiO
2. A direct-fitting procedure of the TDS data has been applied to extract the kinetics parameters. The binding energies in the limit of zero coverage decrease as anatase thin film > amorphous-TiNTs ∼ polycrystalline anatase TiNTs > polycrystalline mixed anatase/rutile TiNTs.