Carbon nanotube-based catalysts (Pt, Ru, and Pt-Ru) were developed and compared with their analogues on activated carbon for the selective reduction of cinnamaldehyde to the corresponding unsaturated alcohol. The use of a mesoporous nanostructured support, which makes mass transfer limitations less significant, gave far better activities than microporous activated carbon. A bimetallic system was found to afford a remarkably high selectivity (93%) for high conversion levels (80%), provided that a thermal pretreatment was performed on the catalyst. These results can be rationalized in terms of electron transfer from the support to the metal. (c) 2006 Elsevier Inc. All rights reserved.