Non-precious metal nanotube arrays hybrid catalyst prepared by a mutual template method for efficient water oxidation in alkaline medium

A mutual template route was designed to prepare Ni-P/Fe(OH) 3 -Cu nanotube arrays with a high electrocatalytic activity for OER. In 1.0 M KOH solution, the as-obtained hybrid electrocatalyst required only a low overpotential of 271 mV to achieve a current density of 20 mA cm −2 with a small Tafel slope of 57.7 mV dec −1 . After 1000 CV cycles at the scan rate of 100 mV s −1 , the overpotential of the catalyst hardly increased; and after continuously catalyzing for 130 h at 20 mA cm −2 , the potential only slightly increased, implying that the as-obtained hybrid electrocatalyst possessed excellent cycle stability and long-term stability. The above outstanding electrocatalytic activity should be ascribed to its special tubular structure and the synergicaction between Ni-P alloy and Fe(OH) 3 nanotubes. Moreover, the presence of elemental copper, which was formed by the in-situ electrochemical reduction of Cu(OH) 2 , also enhanced the catalytic performance due to its excellent electrical conductivity.