2 research outputs found
Atomic structure of cobalt oxide nanoparticles active in light driven catalysis of water oxidation
The atomic structure of water-oxidizing nanoparticles (10–60 nm) formed from
cobalt(II) salts and methylenediphosphonate (M2P) is investigated. These
amorphous nanoparticles are of high interest for production of solar fuels.
They facilitate water oxidation in a directly light-driven process using
[Ru(bpy)3]2+ (bpy = 2,2’-bipyridine) as a photosensitizer and persulfate
(S2O82−) as an electron acceptor. By X-ray absorption spectroscopy (XAS) at
the cobalt K-edge, cobalt L-edge and oxygen K-edge, we investigate the light-
driven transition from the CoII/M2P precursor to the active catalyst, which is
a layered cobalt(III) oxide with structural similarities to water-oxidizing
electrocatalysts. The M2P ligand likely binds at the periphery of the
nanoparticles, preventing their further agglomeration during the catalytic
reaction. This system opens a possibility to link the catalytically active
nanoparticles via a covalent bridge to a photosensitizer and build an
artificial photosynthetic system for direct utilization of solar energy for
fuel production without production of electricity as an intermediate step.
This article is part of a Special Issue entitled: Photosynthetic and
Biomimetic Hydrogen Production