Assembly NiFe LDH nanosheets onto eggshell membrane-derived carbon composite as an effective electrocatalyst for the oxygen evolution reaction.

The development of efficient and cost-effective electrocatalysts for the oxygen evolution reaction (OER) holds key to the large-scale production of hydrogen via a water splitting process. In this work, a bio-waste of eggshell membranes (ESMs) is utilized as a feedstock to fabricate Ni x S y -loaded carbon composite, which is further employed as a platform for the assembly of NiFe layered double hydroxides (NiFe LDH) with the aid of sodium dodecylbenzene sulfonate via facile hydrothermal processes. The resulting nanoarchitectures consist of highly amorphous and intercalation-expanded NiFe LDH nanosheets attached to the carbon composite with strong interactions. The as-prepared samples are examined as electrocatalysts for the OER in alkaline electrolytes and the synergistic effects of the components are elucidated. The optimized sample exhibits a current density of 10 mA cm−2 at an overpotential of 266 mV in 0.1 M KOH, which is superior to the most previously reported non-precious-metal based electrocatalysts and even to the commercial IrO 2. Such remarkable catalytic activity is attributed to the in-situ assembly of NiFe LDH with the carbon composite, leading to the strong coupling interaction of the components. The sample shows stable current during the long-term durability tests accompanying with a structural re-construction process. [Display omitted] • A biowaste of eggshell membranes was used as a facile platform to synthesize electrocatalysts. • The OER activity of the samples was optimized by Ni/Fe ratio, support loadings and SDS. • The optimized sample exhibited a current density of 10 mA cm−2 at an overpotential of 266 mV in 0.1 M KOH. • The outstanding catalytic performance was attributed to the synergistic effects of carbon composite and NiFe LDH. [ABSTRACT FROM AUTHOR]