Room temperature adsorption of propene and propane on copper ions distributed in titanate nanotubes

Abstract

Titanate nanotubes containing copper ions are interesting materials that exhibit efficient activity in the selective reduction of nitrogen monoxide and/or in the degradation of dyes. However, research seems to be less concerned about the interaction of these materials with various gas molecules. We investigated the room temperature adsorption of propene and propane onto the copper ion distributed on the titanate nanotubes (Cu2+-T-TiO2). From the adsorption experiments utilizing carbon monoxide, it was apparent that monovalent copper ions are formed in the titanate nanotubes by evacuation at around 473 K. Cu2+-T-TiO2 exhibited more efficient adsorption for propene, in comparison with propane. Fourier transform infrared spectroscopy clearly indicated the interaction of the monovalent copper ions in the titanate nanotubes with propene due to the π back donation interaction between the active centers in the nanotubes and propene.