Phys.org March 26, 2024 To understand the factors that promote bimetallic H–H coupling researchers at the University of North Carolina at Chapel Hill, USA, subjected molecular iridium catalysts to undergo photoelectrochemical dihydrogen (H2) evolution via a bimolecular mechanism. Covalently tethered diiridium catalysts evolved H2 from neutral water faster than monometallic catalysts, even at lower overpotential. The unexpected origin of this improvement was non-covalent supramolecular self-assembly into nanoscale aggregates that efficiently harvested light and form H–H bonds. Monometallic catalysts containing long-chain alkane substituents leveraged the self-assembly to evolve H2 from neutral water at low overpotential and with rates close to the […]
Tag Archives: Water splitting
Light instead of electricity: A new kind of ‘green hydrogen’
Phys.org May 31, 2022 Photocatalytic water splitting concept is not yet used industrially. An international team of researchers (Austria, Germany, Japan) has found a new combination of molecular and solid-state catalysts to transform water into O2 molecules, and hydrogen ions into H2 molecules. They anchored clusters made up of cobalt, tungsten and oxygen for oxidizing oxygen, and clusters of sulfur and molybdenum for creating hydrogen molecules on a surface of light-absorbing support structures such as titanium oxide. The energy of the absorbed light led to the creation of free-moving electrons and free-moving positive charges in the titanium oxide. These charges […]
New approach creates an exceptional single-atom catalyst for water splitting
Phys.org September 1, 2021 Electrolysis could produce fuels and chemical feedstocks more sustainably and reduce the use of fossil fuels. But the sluggish pace of oxygen evolution reaction (OER) has been a bottleneck to improving its efficiency. A team of researchers in the US (Stanford University SLAC National Accelerator Laboratory, Lawrence Berkeley National Laboratory, UC Berkeley, NIST) used operando X-ray absorption spectroscopy measurements to demonstrate that the origin of water oxidation activity of IrNiFe SACs is the presence of highly oxidized Ir single atom in the NiFe oxyhydroxide under operating conditions. They showed that the optimal water oxidation catalyst could […]