One-step synthesis of ultrathin α-Co(OH)₂nanomeshes and their high electrocatalytic activity toward the oxygen evolution reaction

Abstract

Herein, we demonstrate for the first time the one-step synthesis of ultrathin α-Co(OH)2 nanomeshes by an imidazole-directed route. The α-Co(OH)2 nanomeshes combine the advantages of ultrathin thickness (3 nm), small mesopores (3.7 nm), large specific surface area (181.1 m2 g-1) and high surface oxygen vacancy density, which exhibit excellent electrocatalytic performance for the oxygen evolution reaction.

Spontaneous Synthesis of Silver‐Nanoparticle‐Decorated Transition‐Metal Hydroxides for Enhanced Oxygen Evolution Reaction

“…[8] For example, the large interlayer spacing and nanosheet (NS) structure of Co(OH) 2 are conducive to facilitate ion transport and provide large active area, respectively, which is vital to accelerate the OER kinetics in alkaline electrolytes. [9] However, Co(OH) 2 NS working as the anode catalyst of water electrolysis still cannot achieve ideal overpotential (lower than 300 mV at 10 mA cm À2 ), [10] indicating that the intrinsic activity of catalytic sites in Co(OH) 2 NS is limited. Consequently, it is critical to improve the catalytic efficiency and decrease the overpotential of Co(OH) 2 NS by engineering the surface atomic and electronic structures.…”

Spontaneous Synthesis of Silver‐Nanoparticle‐Decorated Transition‐Metal Hydroxides for Enhanced Oxygen Evolution Reaction

“…[8] For example, the large interlayer spacing and nanosheet (NS) structure of Co(OH) 2 are conducive to facilitate ion transport and provide large active area, respectively, which is vital to accelerate the OER kinetics in alkaline electrolytes. [9] However, Co(OH) 2 NS working as the anode catalyst of water electrolysis still cannot achieve ideal overpotential (lower than 300 mV at 10 mA cm À2 ), [10] indicating that the intrinsic activity of catalytic sites in Co(OH) 2 NS is limited. Consequently, it is critical to improve the catalytic efficiency and decrease the overpotential of Co(OH) 2 NS by engineering the surface atomic and electronic structures.Integrating metal nanoparticles with transition-metal compounds has been explored as a promising strategy to synthesize highly efficient electrocatalysts.…”

Facile Synthesis of 3d Transition-Metal-Doped α-Co(OH)2 Nanomaterials in Water–Methanol Mediated with Ammonia for Oxygen Evolution Reaction

“…However, by replacing water with water–methanol solution, homogeneous green dispersion can be obtained within 30 min, which presented the typical UV–vis absorption peaks of α-Co(OH) 2 at 586 and 642 nm (the inset of Figure 1a). 31 The characteristic X-ray diffraction (XRD) peaks of α-Co(OH) 2 at 9.6°, 19.3°, 33.4°, and 59.6° correspond to the lattice distances of (003), (006), (012), and (110) planes of α-Co(OH) 2 (JCPDS no. 46-0605) (Figure 1a).…”

“…29,30 Ultrathin α-Co(OH) 2 nanostructures were prepared through 2-methylimidazole-mediated methods with good to excellent electrocatalytic activity. 31−33 Transition-metal doping has also been proved as an efficient method to improve the electrocatalytic activity of Co(OH) 2 . 34−37 Copper- or iron-doped Co(OH) 2 has been respectively reported to effectively catalyze water oxidation at the overpotential around 300 mV at 10 mA cm –2 current density with the former synthesized via NaBH 4 reducing method and the latter precipitated with NaOH in the presence of NaNO 3 , NH 4 F, and sodium citrate under N 2 atmosphere.…”