A molecular material based on electropolymerized cobalt macrocycles for electrocatalytic hydrogen evolution

作者：Rioual Stephane; Lescop Benoit; Quentel Francois; Gloaguen Frederic^*

来源：Physical Chemistry Chemical Physics, 2015, 17(20): 13374-13379.

DOI：10.1039/c5cp01210d

An electrocatalytic material for the H-2 evolution reaction (HER) in acidic aqueous solution has been prepared by electropolymerization of Co(II) dibenzotetraaza[14] annulene (CoTAA). Chemical analysis by X-ray photoelectron spectroscopy (XPS) confirms that the structural integrity of the [Co-II-N-4] motif is preserved in the poly-CoTAA film. In acetate buffer solution at pH 4.6, an overpotential eta = -0.57 V is required to attain a catalytic current density -i(k) = 1 mA cm(geom)(-2). The faradaic efficiency of poly-CoTAA for the HER is 90% over a period of one hour of electrolysis, but there is a decrease of the apparent concentration of Co sites after prolonged H2 production, which we ascribe to partial demetallation of the poly-CoTAA film at negative potentials.

• 出版日期2015