Sea urchin-like lanthanum decorated Ni3S2@FeOOH for boosting oxygen evolution catalysis in simulated seawater electrolysis

Abstract

In the field of hydrogen energy development and exploration, the development of energy-saving, environmentally friendly, highly efficient and practical hydrogen production catalysts is of utmost importance for the development of energy fields. In this work, a sea urchin-like nanocluster electrocatalyst (La-Ni₃S₂@FeOOH) was successfully synthesized on a nickel foam substrate. The prepared catalyst exhibits good electrochemical performance in a simulated seawater electrolyte. It has relatively low overpotentials of 249 mV and 367 mV at current densities of 10 mA cm⁻² and 50 mA cm⁻², respectively. Additionally, the Tafel slope is 39.13 mV dec⁻¹ at 10 mA cm⁻²; it has a large electrochemically active surface area and a small electrochemical impedance, and remains stable during a long-term stability test for 100 hours. The excellent performance of the catalyst is likely due to the incorporation of rare earth element La, which promotes the occurrence of redox reactions and thus optimizes the electronic structure of materials. Moreover, the unique surface morphology not only provides a large number of active sites, but also effectively promotes the infiltration of the electrolyte on the surface of the catalyst and the desorption of bubbles. This method provides a new idea for the development of economical and environmentally friendly electrocatalysts for the oxygen evolution reaction.