The development of a cost-effective
and easy-to-prepare oxygen
evolution reaction (OER) catalyst for electrolyzers at large current
density is highly desired. Herein, we designed a convenient strategy
to fabricate a three-dimensional self-supported S2–-doped NiFe layered double hydroxide (NiFe-LDH)/Ni foam (NF) catalyst
by a hydrothermal reaction and etching at ambient temperature. The
as-obtained S2–-doped NiFe-LDH/NF (NiFe-LDH/NF-S-3h)
with hierarchical porous nanosheets is beneficial for providing high
density of active sites and accelerating the mass transport. Remarkably,
NiFe-LDH/NF-S-3h exhibits a superior activity for the OER with a very
low overpotential of 239 and 309 mV to deliver current densities of
100 and 500 mA cm–2 in alkaline medium. Additionally,
NiFe-LDH/NF-S-3h also demonstrates excellent long-term stability at
500 mA cm–2 for 150 h, showing an excellent industrial
application prospect. Moreover, density functional theory calculations
and X-ray absorption spectroscopy reveal that the introduction of
S2– can effectively optimize the electronic structure
of the cationic active site and improve the adsorption and desorption
capability of oxygenated intermediates. The present work may provide
a relatively convenient method for designing highly active electrocatalysts
for practical applications.