Tracking the pyrolysis process of a 3-MeOsalophen-ligand based Co₂ complex for promoted oxygen evolution reaction.

ABSTRACT: Efficient oxygen evolution reaction catalysts can be prepared via controlled pyrolysis of molecular platforms, and there is still minimal mechanistic understanding of such pyrolysis processes. Here, we introduce a 3-MeOsalophen-ligated cobalt complex as a precursor to obtain a Co-based OER electrocatalyst via controlled pyrolysis under an inert atmosphere. In our case, the unique N, O chelation mode of the 3-MeOsalophen ligand (bis[3-methoxysalicylydene]-1,2 iminophenylenediamine) was used to synthesis a Co₂ complex [Co₂(3-MeOsalophen)(Cl)₃(CH₃OH)₂]. By regulating the pyrolysis conditions, we successfully obtained a N-doped carbon Co/CoO _x core-shell nanostructure. More importantly, TG-MS was first adopted for tracking the decomposition products of the complex in the pyrolysis process, further finding out the evolution mechanism from Co₂ to the core-shell nanostructure. As an electrocatalyst for the oxygen evolution reaction, the core-shell Co/CoO _x @NC-800 nanostructure achieves an ultralow overpotential of 288 mV at 10 mA cm^-2 in 1 M KOH solution. This work offers guiding insight into controlled pyrolysis via TG-MS analysis, using a novel complex precursor for precise regulation of heteroatom-doped (3d) transition metal-based electrocatalysts.

SUBMITTER: Pan B 

PROVIDER: S-EPMC6492634 | biostudies-literature | 2019 May

REPOSITORIES: biostudies-literature