Green Preparation of CNTs/Graphite Supported NiFe Carbonate Hydroxides for Oxygen Evolution Reaction

Abstract Developing durable and highly active non‐noble electrocatalysts for oxygen evolution reaction (OER) is highly desirable for water splitting. Herein, we report a NiFe carbonate hydroxides embedded in a carbon nanotubes and graphite composite material (NiFe CHs‐CNT/G) by a facile and green precipitation method. The NiFe CHs are in‐situ grown on CNT/G using NH 3 ⋅H 2 O as precipitant and CO 2 in air as the source of CO 3 2− under room temperature and pressure. The introduction of CNT/G not only improves the conductivity of material, but also enhances the combination of CNT/G and NiFe CHs nanosheets, thereby accelerating the transfer of electrons and reactants. Meanwhile, the catalyst with a special sandwich morphology provides larger active area to expose more active sites. Moreover, the effective interaction within the Ni and Fe in NiFe CHs‐CNT/G is benefiting for improving OER performance. All these lead to the optimized NiFe CHs‐CNT/G catalyst delivers an outstanding OER performance with a low overpotential of 300 mV at 10 mA cm −2 and a small Tafel slope of 60.13 mV dec −1 .