Unexpected Adsorption of Oxygen on TiO2 Nanotube Arrays:  Influence of Crystal Structure

• Published in: Nano letters 2007-04, Vol.7 (4), p.1091-1094
• Main Authors: Funk, S, Hokkanen, B, Burghaus, U, Ghicov, A, Schmuki, P
• Format: Article
• Language: English
• Subjects: Adsorption; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Crystallization - methods; Exact sciences and technology; Macromolecular Substances - chemistry; Materials science; Materials Testing; Molecular Conformation; Nanoscale materials and structures: fabrication and characterization; Nanoscale materials: clusters, nanoparticles, nanotubes, and nanocrystals; Nanotechnology - methods; Nanotubes; Nanotubes - chemistry; Nanotubes - ultrastructure; Oxygen - chemistry; Particle Size; Physics; Solid surfaces and solid-solid interfaces; Structure of solids and liquids; crystallography; Structure-Activity Relationship; Surface Properties; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); Titanium - chemistry
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl062797j

We present kinetics data of O2, n/iso-butane, CO2, and CO adsorbed at ultrahigh vacuum conditions on TiO2 nanotube (TiNTs) arrays produced by electrochemical anodization; amorphous and polycrystalline (anatase and mixed anatase/rutile) TiNTs have been studied addressing structure−activity relationships. Oxygen distinctly interacts with the TiNTs, whereas this process is not observed on fully oxidized TiO2 single crystals. Both molecularly and atomically bonded oxygen have been observed. Variations in the binding energies of alkanes were also detected.