Fe and Pt carbon nanotubes for the electrocatalytic conversion of carbon dioxide to oxygenates

Using Pt/CNT or Fe/CNT electrocatalysts it is possible to convert carbon dioxide to liquid fuels, particularly isopropanol. Fe/CNT shows a better behavior than Pt/CNT, although a faster deactivation. The main reason of deactivation is cross-over of the electrolyte, particularly of K ions. They react with iron particles and cause their dissolution and migration. In the case of Pt/CNT there is no, or minor, dissolution of metal, but potassium covers the Pt particles and/or induce deactivation. It is shown, however, that the electrolyte was necessary to Simulate the half-cell of the full photoelectrocatalytic device, while in the latter no electrolyte is needed, being the protons and electrons produced by water splitting. The elimination of the electrolyte probably could eliminate or significantly reduce a main Cause determining the observed fast deactivation. (C) 2008 Elsevier B.V. All rights reserved.