Electrochemical Reduction of CO 2 in the Micropores of Activated Carbon Fibers

Abstract

electroreduction was examined on high‐area metal (Fe, Ni, Cu, Pd) electrocatalysts supported on activated carbon fibers (ACF), which contain slit‐shaped pores with widths on the order of 2 nm. These catalysts exhibited relatively high selectivity (ca. 67% total current efficiency for reduction on ACF/Ni) and high partial current density (up to for reduction on ACF/Ni). Much smaller activities were observed for the same types of metal catalysts supported on nonactivated carbon fibers. The enhancement of the reduction selectivity with the microporous support is thought to involve a nanospace effect, which gives rise to high‐pressure‐like effects at ambient pressure. The reduction mechanism on Ni is proposed to involve an adsorbed adduct, which is known to exist on the (110) surface. © 2000 The Electrochemical Society. All rights reserved.