CoOOH Nanosheets with High Mass Activity for Water Oxidation

Abstract

Endowing transition-metal oxide electrocatalysts with high water oxidation activity is greatly desired for production of clean and sustainable chemical fuels. Here, we present an atomically thin cobalt oxyhydroxide (γ-CoOOH) nanosheet as an efficient electrocatalyst for water oxidation. The 1.4 nm thick γ-CoOOH nanosheet electrocatalyst can effectively oxidize water with extraordinarily large mass activities of 66.6 A g(-1), 20 times higher than that of γ-CoOOH bulk and 2.4 times higher than that of the benchmarking IrO2 electrocatalyst. Experimental characterizations and first-principles calculations provide solid evidence to the half-metallic nature of the as-prepared nanosheets with local structure distortion of the surface CoO(6-x) octahedron. This greatly enhances the electrophilicity of H2O and facilitates the interfacial electron transfer between Co ions and adsorbed -OOH species to form O2, resulting in the high electrocatalytic activity of layered CoOOH for water oxidation.

Facile synthesis of Fe/Ni bimetallic oxide solid-solution nanoparticles with superior electrocatalytic activity for oxygen evolution reaction

“…In the case of inorganic salts as precursors, a few metal hydroides may have formed through metal ion hydrolysis during solvent evaporation. It is well known that metal hydroxides easily grow into nanosheets owing to their layered structure [15,21,31,32]. Because solvent evaporation is much faster than the hydrolysis of metal ions, the proportion of nanosheets is much lower than that of nanoparticles in the microspheres formed by the subsequent pyrolysis of nitrates.…”

Sub-1.1 nm ultrathin porous CoP nanosheets with dominant reactive {200} facets: a high mass activity and efficient electrocatalyst for the hydrogen evolution reaction

“…27–36 For example, greatly enhanced catalytic performances have been achieved by the pioneering 2D ultrathin nanosheets made by the Xie, 27–30 Wei, 27,28,31 Yang 32 and Zhang 33,34 groups. A huge mass activity for the oxygen evolution reaction has been achieved by well-designed ultrathin CoOOH solid nanosheets.…”

Electrochemical Partial Reforming of Ethanol into Ethyl Acetate Using Ultrathin Co3O4 Nanosheets as a Highly Selective Anode Catalyst

“…It should be noted that the overpotential on Co 3 O 4 NSs was also lower than that for many previously reported Co-based catalysts. 19,34,35,43 Moreover, the corresponding Tafel plots (Figure 3c) indicated that the ultrathin Co 3 O 4 NSs possessed a smaller Tafel slope (46 mV/dec) than that of Co 3 O 4 NCs (63 mV/dec). The smaller Tafel slope makes Co 3 O 4 NSs have large current densities at low overpotentials.…”