Improved electrocatalytic effect of carbon nanomaterials by covalently anchoring with CoTAPP via diazonium salt reactions

Cobalt[tetrakis(o-aminophenyl)porphyrin] (CoTAPP) was covalently anchored (CA) onto the surface of three carbon nanomaterials (CNMs: graphene, single-walled carbon nanotubes (SWCNT), and multi-walled carbon nanotubes (MWCNT)) via diazonium salt reactions, which is a simple and effective method to improve the electrocatalytic activity of CoTAPP for combination with CNMs. The electrocatalytic reduction of O-2 on glassy carbon electrodes (GCEs) modified with these CoTAPP-anchored CNMs established a pathway of four-electron transfer reductions to H2O. Among the CoTAPP-anchored CNMs, anchored graphene with CoTAPP showed the best electro-catalytic effect and the most efficient electrocatalytic performance for oxygen reduction reaction (ORR) without any precious metals. (C) 2012 Elsevier B.V. All rights reserved.