Mixed Metal Fe 2 Ni MIL-88B Metal-Organic Frameworks Decorated on Reduced Graphene Oxide as a Robust and Highly Efficient Electrocatalyst for Alkaline Water Oxidation.

The development of cost-effective and efficient oxygen evolution reaction (OER) catalysts has found increasing popularity due to the sluggish kinetics of OER, which has hampered the H 2 production by H 2 O electrolysis. In this study, Fe 2 Ni MIL-88 (denoted FeNi) was composited by reduced graphene oxide (rGO, denoted R). Owing to the high porosity and abundant active sites of bimetallic MOF, proper conductivity of rGO, and the synergistic impact of Ni and Fe, the optimal composite (R@FeNi (1:1)) offered remarkable OER activity in alkaline environments. The obtained composite was employed in the OER, which led to a low overpotential of 264 mV at a current density of 10 mA cm -2 with a Tafel slope of 62 mV dec -1 . Also, the bimetallic Fe 2 Ni MIL-88 nanorods grown on rGO led to a reduction in the onset potential of the OER. These findings exceeded the results of standard IrO 2 -based catalysts; they are also comparable or even better than the previously reported MOF-based catalysts.