Homogeneous Photochemical Water Oxidation with Cobalt
Chloride in Acidic Media
- Publication date
- Publisher
Abstract
The
precise mechanisms of four-electron-transfer water oxidation processes
remain to be further understood. Oxide-based precipitation from molecular
catalysts as a frequent observation during water oxidation has raised
extensive debates on the differentiation between homogeneous and heterogeneous
catalysis. Although soluble cobalt salts are known to be active in
water oxidation, CoO<sub><i>x</i></sub> species formed in
situ were generally considered to be the true catalyst. Here we report
on the possibility homogeneous water oxidation with cobalt chloride
in acidic conditions, which prevent CoO<sub><i>x</i></sub> precipitation. Interestingly, both the buffer media and counteranions
were found to significantly influence the oxygen evolution activity,
and their roles in the water oxidation process were analyzed with
various techniques. This study sheds new light on Co<sup>2+</sup> ions
in key transformation processes of homogeneous water oxidation catalysts