Convenient Immobilization of Cobalt Corroles on Carbon Nanotubes through Covalent Bonds for Electrocatalytic Hydrogen and Oxygen Evolution Reactions

Two different methods were used to immobilize Co corroles on carbon nanotubes (CNTs) through covalent bonds. The resulting CNTs engineered with Co corroles were used as electrocatalysts for the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) in aqueous solutions of pH 0, 7, and 14. For both HER and OER in all solutions, the hybrids obtained by attaching Co corroles on CNTs through amidation coupling showed better performance. This is likely because the large surface area and good electrical conductivity of CNTs can be well preserved during the amidation reaction under mild conditions.