posted on 2021-11-04, 15:34authored byFeifei Yuan, Enli Zhang, Zihao Liu, Kun Yang, Qingqing Zha, Yonghong Ni
Hollow CoSx nanoparticles grown on
FeCo-LDH microtubes (FeCo-LDH@CoSx) were
successfully developed as a highly efficient and low-cost electrocatalyst
for the oxygen evolution reaction (OER) in an alkaline solution. The
as-prepared FeCo-LDH@CoSx microtubes were
characterized by X-ray powder diffraction, field emission scanning
electron microscopy, transmission electron microscopy, energy-dispersive
X-ray spectroscopy (EDS), X-ray photoelectron spectroscopy, and high-angle
annular dark-field scanning transmission electron microscopy (HAADF-STEM)-EDS
elemental mapping. Experiments showed that the as-obtained hollow
FeCo-LDH@CoSx electrocatalyst required
low overpotentials of 229, 270, and 308 mV to deliver current densities
of 10, 100, and 400 mA cm–2 in a 1 M KOH distilled
water solution, respectively. Also, the as-obtained catalyst exhibited
good durability in various alkaline electrolytes, including distilled
water, tap water, and natural river water. In a two-electrode water-splitting
device with nickel foams separately coated by FeCo-LDH@CoSx and 20% Pt/C as the anode and the cathode,
respectively, using distilled water as the electrolyte, voltages of
1.495, 1.600, and 1.785 V were separately required for achieving current
densities of 10, 100, and 400 mA cm–2. Simultaneously,
the present two-electrode system continuously worked for 50 h at a
current density of 50 mA cm–2 in various alkaline
electrolytes, including distilled water, tap water, and natural river
water, and no obvious voltage fluctuation was detected, implying remarkable
stability. Obviously, the present FeCo-LDH@CoSx microstructure provides a catalyst selection for the OER
in practical applications.