Hollow CoS_x Nanoparticles Grown on FeCo-LDH Microtubes for Enhanced Electrocatalytic Performances for the Oxygen Evolution Reaction

Abstract

Hollow CoS x nanoparticles grown on FeCo-LDH microtubes (FeCo-LDH@CoS x ) were successfully developed as a highly efficient and lowcost electrocatalyst for the oxygen evolution reaction (OER) in an alkaline solution. The as-prepared FeCo-LDH@CoS x 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@CoS x 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 twoelectrode water-splitting device with nickel foams separately coated by FeCo-LDH@CoS x 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@CoS x microstructure provides a catalyst selection for the OER in practical applications.

Hollow CoNiS polyhedrons/MnCoNi layered double hydroxide nanorod arrays on nickel foam as integral electrodes for improved oxygen evolution reaction in alkaline media

“…It was found that Ni atoms on the surface of nickel foam entered into the formation of MnCo LDH nanoneedle arrays 23 . Also, our work proved that LDHs were not sulfurized under proper sulfurization conditions 24 . In the current work, therefore, we attempted to construct a hybrid electrocatalyst consisted of hollow Co 9 S 8 polyhedrons and MnCo LDH nanoneedle arrays on nickel foam for the OER.…”

“…23 Also, our work proved that LDHs were not sulfurized under proper sulfurization conditions. 24 In the current work, therefore, we attempted to construct a hybrid electrocatalyst consisted of hollow Co 9 S 8 polyhedrons and MnCo LDH nanoneedle arrays on nickel foam for the OER. Firstly, ZIF-67 polyhedrons loaded on the preprepared NF-supported MnCo LDH nanoneedle arrays; then, the above arrays were sulfurized to form the final product.…”

Sequential galvanic replacement mediated Pd-doped hollow Ru–Te nanorods for enhanced hydrogen evolution reaction mass activity in alkaline media

“…These results indicate that the PdRuTeNR electrocatalyst allows more effective accessibility of its electrocatalytic active sites. [36][37][38][39] Additionally, we conducted CV studies on Pd, Ru and RuO 2 to look into the reduction potential of our suggested PdRuTeNRs (Fig. S4 †).…”

Dual-Metal Zeolitic Imidazolate Framework Derived Highly Ordered Hierarchical Nanoarrays on Self-Supported Carbon Fiber for Oxygen Evolution

“…OER performance of recently reported CoFe bimetallic powder catalyst. References [36][37][38][39][40][41][42][43][44][45][46][47][48][49][50] are cited in the supplementary materials.…”