Nickel cobalt oxide nanowires with iron incorporation realizing a promising electrocatalytic oxygen evolution reaction

Abstract

Developing cost-effective electrocatalysts for water electrolysis is a promising strategy to enhance conversion and storage efficiency of sustainable energy. Transition metal oxides have been considered as alternative oxygen evolution reaction (OER) catalysts to replace noble metal-based catalysts. Here, we report a series of Fe-doped NiCo 2 O 4 (NCO) nanowires with different Fe-doped concentrations, synthesized by a facile solvothermal and calcinations process, as high-efficiency electrocatalysts for OER. Due to abundant catalytically active sites, high-charge transport capability and specific surface area, these as-obtained NCO nanowires exhibit low overpotential and small Tafel slope. Specifically, NCO-0.1 shows the outstanding OER performance with a low overpotential of 297 mV at a current density of 10 mA cm −2 and a small Tafel slope of about 68 mV dec −1 in 1.0 M KOH. This study offers a promising electrocatalyst for the OER in water splitting.

Iron‐Doped NiCo2O4 Nanoparticles: Synthesis via Homogeneous Precipitation Method and Studies on their Peroxidase‐like Activity

“…The shift suggests successful incorporation of Fe 3 + in NiCo 2 O 4 nanoparticles. Similar shift in XRD peaks in Fe-doped NiCo 2 O 4 nanowires has been reported by Hao et al [31] The crystallite size of pure NiCo 2 O 4 and iron-doped NiCo 2 O 4 nanoparticles was estimated using Scherrer formula and the values for pure NiCo 2 O 4 , FeNC-0.1-500, FeNC-0.3-500, FeNC-0.5-500 and FeNC-0.7-500 are 13.4 nm, 11.7 nm, 12.6 nm, 10.1 nm and 12.4 nm, respectively. Figure S8 depicts the Rietveld refinement of XRD patterns of iron-doped NiCo 2 O 4 nanoparticles.…”

“…Hao et al have reported such shift towards higher binding energy after the introduction of iron in NiCo 2 O 4 nanowires. [31] The DRS results of pure NiCo 2 O 4 nanoparticles and irondoped NiCo 2 O 4 nanoparticles are depicted in Figure 6. Figure S14 shows the Tauc plots from which the band gaps of NiCo 2 O 4 and iron-doped NiCo 2 O 4 nanoparticles were determined.…”

“…There are only a few reports on the synthesis of Ni 1À x Fe x Co 2 O 4 nanoparticles. [29][30][31][32][33] The reported solvothermal methods for the synthesis of iron-doped NiCo 2 O 4 nanoparticles require high temperature (120 °C-180 °C), long reaction time (6-20 h) and a teflon-lined autoclave. In the present study, the synthesis of iron-doped NiCo 2 O 4 nanoparticles has been carried out using homogeneous precipitation method, which is costeffective and easy.…”

Djurleite Copper Sulfide-Coupled Cobalt Sulfide Interface for a Stable and Efficient Electrocatalyst

“…Stability is used to evaluate the performance of electrocatalysts over a long period of time. The stability test was done by the constant current method (chronopotentiometry). − …”

Surface oxidation of cobalt carbonate and oxide nanowires by electrocatalytic oxygen evolution reaction in alkaline solution

“…In particular, for the cobalt-related materials, the nanowire structures with a large surface area and promoted electric current have been suggested cardinally for water electrolysis [21][22][23][24][25][26]. The well-defined 1D nanowire arrangements enable a new configuration of highefficiency electrocatalyst/electrode due to synergistic effects such as faster electrolyte penetration and diffusion of ionic species, greater electrical conductivity, higher structural stability, and short electron transport pathway [23,[27][28][29][30]. Recently, the surface oxidation reaction for cobalt nanorod arrays was reported to be able to improve electrocatalytic properties [31].…”