Amorphous CoFe Double Hydroxides Decorated with N-Doped CNTs for Efficient Electrochemical Oxygen Evolution.

Abstract

The development and design of a highly active and affordable nanostructured material as an efficient electrocatalyst for electrochemical oxygen evolution is a pressing necessity to realize industrial production of hydrogen by water electrolysis. Amorphous nanocomposites have recently attracted interest owing to their superior electrocatalytic activity derived from their unique structure. Herein, amorphous CoFe double hydroxides (Am-CFDH) decorated with N-doped carbon nanotubes (NCNTs) is synthesized by a facile and simple one-pot approach under room temperature. Through electrochemical measurement, the bare Am-CFDH nanocomposite already exhibits a comparable oxygen evolution reaction (OER) activity to the commercial IrO2 catalyst on account of its amorphous nature and the interaction between Co and Fe. The introduced NCNTs can provide better electrical conductivity, more anchoring sites, and functional groups for enhancing the transfer of electrons and reactants, preventing the agglomeration of Am-CFDH to expose more active sites, and improving the synergistic effect between Am-CFDH and NCNTs. Thus, the Am-CFDH/NCNTs hybrid displays favorable durability beyond 20 h and advanced OER activity, owning a small overpotential of 270 mV at 10 mA cm-2 and a low Tafel slope of 56.88 mV dec-1 in alkaline medium.