Multiple oxyanions modification on nickel–iron layered double hydroxides for enhanced oxygen evolution reaction.

The electrochemical oxygen evolution reaction (OER) holds paramount significance as a pivotal stage within electrochemical water-splitting processes, particularly in hydrogen production. Highly efficient OER electrocatalysts with inherent capability to effectively lower the energy barrier and promote fast kinetics are in high demand. In this research, we have introduced a novel strategy of modifying the non-precious metal benchmark catalyst, NiFe layered double hydroxide (LDH), through multiple oxyanions. Our approach involved incorporating MoS 4 2− as a source of modified anions to enhance the performance of LDH in OER. Under specific conditions of the hydrothermal reaction, a majority of the sulfur (S) within the MoS 4 2− anions underwent oxidization, resulting in the formation of SO 4 2− and MoO x S 4-x 2- groups. As a result, NiFe LDH composites that were modified with multiple oxyanionic moieties, were successfully fabricated. Thanks to the synergistic effects of these oxyanions, which accelerate the generation of active NiOOH species, the optimized NiFe LDH-MoS 4 -0.1/NF sample exhibited a significantly low overpotential of 228 and 270 mV at current densities of 10 and 100 mA cm−2, respectively, along with a low Tafel slope of 35.5 mVdec−1 in 1 M KOH electrolyte solution. Our study underscored the importance of embracing diverse oxyanions modification strategy to amplify the performance of OER, opening up numerous opportunities for energy conversion and storage applications. A multiple oxyanions modification strategy was proposed for enhancing the OER performance of NiFe layered double hydroxide (LDH) materials via introducing MoS 4 2− as modified anion sources. Thanks to the synergistic effects of multiple oxyanions (SO 4 2− and MoO x S 4-x 2-), the optimized sample exhibited a remarkable OER activity. [Display omitted] • NiFe LDH materials modified with multiple oxyanions via hydrothermal synthesis. • Multiple oxyanions (SO 4 2− and MoO x S 4-x 2-) originated from MoS 4 2− degradation. • The optimized NiFe LDH-MoS 4 -0.1/NF sample showed outstanding OER activity. [ABSTRACT FROM AUTHOR]