Electrocatalytic water oxidation by a molecular cobalt complex through a high valent cobalt oxo intermediate.

Time-resolved observations of water oxidation intermediates on a cobalt oxide nanoparticle catalyst.

In any artificial photosynthetic system, the oxidation of water to molecular oxygen provides the electrons needed for the reduction of protons or carbon dioxide to a fuel. Understanding how this four-electron reaction works in detail is important for the development of improved robust catalysts made of Earth-abundant materials, like first-row transition-metal oxides. Here, using time-resolved F...

Interrogation of electrocatalytic water oxidation mediated by a cobalt complex.

Examination of the aqueous electrochemistry of a Co(II) complex bearing a pentadentate ligand suggests that the catalytic current corresponding to water oxidation is molecular in origin, and does not emanate exclusively from Co-oxide phases formed in situ.

Synthesis and reactivity of a mononuclear non-haem cobalt(IV)-oxo complex

Terminal cobalt(IV)-oxo (CoIV-O) species have been implicated as key intermediates in various cobalt-mediated oxidation reactions. Herein we report the photocatalytic generation of a mononuclear non-haem [(13-TMC)CoIV(O)]2+ (2) by irradiating [CoII(13-TMC)(CF3SO3)]+ (1) in the presence of [RuII(bpy)3]2+, Na2S2O8, and water as an oxygen source. The intermediate 2 was also obtained by reacting 1 ...

Dinitrogen activation by a low - valent cobalt complex and the elusive cobalt - oxo

Synthetic control and empirical prediction of redox potentials for Co4O4 cubanes over a 1.4 V range: implications for catalyst design and evaluation of high-valent intermediates in water oxidation† †Electronic supplementary information (ESI) available. CCDC 1532026–1532032. For ESI and crystallographic data in CIF or other electronic format see DOI: 10.1039/c7sc00627f Click here for additional data file. Click here for additional data file.

The oxo-cobalt cubane unit [Co4O4] is of interest as a homogeneous oxygen-evolution reaction (OER) catalyst, and as a functional mimic of heterogeneous cobalt oxide OER catalysts. The synthesis of several new cubanes allows evaluation of redox potentials for the [Co4O4] cluster, which are highly sensitive to the ligand environment and span a remarkable range of 1.42 V. The [Co 4O4] /[Co 3 Co O4...