MO_x@VO_x‐Pd‐type Nanorods and Nanotubes as Catalysts for Selective Reduction of NO

Abstract

Vanadium oxide (VO x -Pd) nanotubes as well as VO x -coated ZnO nanorods (ZnO@VO x -Pd) and VO x -coated, layered-titania nanotubes (l-TiO 2 @VO x -Pd) are decorated with Pd nanoparticles and evaluated for selective catalytic reduction with hydrogen (H 2 -SCR) for the first time. The nanostructures exhibit lengths of 300 to 700 nm, diameters of 20-100 nm and, in the case of the nanotubes, an inner tube diameter of about 10 nm. Pd nanoparticles (14 � 5 nm) are well-dispersed over the respective nanorod/nanotube nanostructure. Structure and composition are characterized by SEM, TEM, EDXS with element mapping, XPS, FT-IR, XRD, and sorption analysis. Thermal analysis indicates the nanostructures to be thermally stabile up to 350 °C (VO x ), and 500 °C (ZnO@VO x , l-TiO 2 @VO x ). All catalysts are tested for their activity in regard of the selective catalytic reduction of NO with H 2 , revealing a significant impact of the catalyst support on both activity and selectivity. Specifically, l-TiO 2 @VO x nanotubes show promising properties with an activity up to 70 % and a selectivity up to 80 % N 2 .