As a reactivity screening we collected thermal desorption spectroscopy (TDS) data of iso-butane, O2, CO2, and CO adsorbed on ordered TiO2 nanotube (TiNTs) arrays. As a reference system iso-butane adsorption on an anatase TiO2 thin film has been considered as well. The as-grown TiNTs are vertically aligned and amorphous. Polycrystalline (poly.) anatase or poly. anatase/rutile mixed nanotubes are formed by annealing confirmed by x-ray diffraction (XRD) and scanning electron microscopy (SEM). The anatase thin film was grown on SrTiO3(001) and characterized by XRD and atomic force microscopy (AFM). Surprisingly, oxygen distinctly interacts with the TiNTs whereas this process is not observed on fully oxidized single crystal rutile TiO2(110). Desorption temperatures of 110-150 K and 100-120 K were observed for CO2 and CO, respectively, on the TiNTs. Variations in the binding energies of the alkanes on TiNTs and anatase thin films also were present, i.e., a structure-activity relationship (SAR) is evident.
Revised: April 7, 2011 |
Published: September 19, 2008
Citation
Funk S., B. Hokkanen, T. Nurkic, J. Goering, E. Kadossov, U. Burghaus, and A. Ghicov, et al. 2008.Reactivity Screening of Anatase TiO2 Nanotube Arrays and Anatase Thin Films: A Surface Chemistry Point of View. In Nanoparticles: Synthesis, Stabilization, Passivation, and Functionalization, ACS Symposium Series. 139-151. Washington, D.C.:American Chemical Society.PNNL-SA-54075.