Applied Catalysis B: Environmental, Vol.188, 169-176, 2016
Enhanced electrocatalytic hydrogen evolution reaction: Supramolecular assemblies of metalloporphyrins on glassy carbon electrodes
Chemically modified electrodes formed by pi-stacking of metalloporphyrins provide a stable and efficient electrocatalytic system for the hydrogen evolution reaction at pH 7.0. Metalloporphyrins M-OEP (M = Co(II), Cu(II), Zn(II), Ru(II), Fe(III) and Ni(II), OEP=2,3,7,8,12,13,17,18-Octaethyl-21H,23H-porphine) were deposited on glassy carbon electrodes that had been previously modified by using NaOH and 4-aminopyridine, which served as a bridging molecule between the metalloporphyrins and the electrode surface. Different supramolecular architectures, as revealed by AFM and SEM, were obtained with bare and oxidized glassy carbon electrode surfaces. The most active systems were those obtained with Co(II) and Cu(II) porphyrins. Raman spectra showed the presence of the linking molecules and metalloporphyrins in the electrocatalytic metalloporphyrin films. (C) 2016 Elsevier B.V. All rights reserved.
Keywords:Hydrogen evolution reaction;Metalloporphyrins;Glassy carbon electrodes;Supramolecular system;Graphene