Catalytic H₂ Evolution with CoO, Co(OH)₂ and CoO(OH) Nanoparticles Generated from a Molecular Polynuclear Co Complex

Abstract

Electrochemical water reduction by employing firstrow transition-metal nanoparticles (NPs) constitutes a sustainable way for the generation of H 2 . We have synthesized Cobased NPs from a molecular Co II /Co III precursor after its reductive decomposition at -1.86 V versus NHE in different organic solvents. These NPs are able to electrochemically reduce water at pH 14. SEM, EDX and XPS analyses have allowed the determination of the chemical nature of the as-deposited NPs: CoO when using MeCN as the solvent and CoO(OH) when employing [a]

Selective Synthesis of Monodisperse CoO Nanooctahedra as Catalysts for Electrochemical Water Oxidation

“…The control of size and morphology is crucial as they determine the surface structure of nanocrystals. The ability to engineer nanocrystal size may ultimately allow the tuning of solid state reactivity, e.g., for electrode materials or catalytic reactivity and selectivity (water-splitting reactions). − This is valuable when preparing colloidal nanocrystals with metal oxides because the interplay between reactivity and surface structure is well-understood from single-particle studies (TiO 2 , MnO, Fe 3 O 4 , CoO, Co 3 O 4 , ZnO). − Many metal oxides are employed as catalysts in a large number of industrial-scale catalytic processes. , Cobalt monoxide (CoO) nanoparticles are significant because of their potential application based on magnetic, catalytic, and gas-sensing properties. − CoO adopts the rock-salt structure and is antiferromagnetic. Particle size and crystal structure affect its magnetic properties.…”