Preprints are openly available non-peer-reviewed manuscripts that precede the actual peer-reviewed publication. We analyse this phenomenon that is gaining popularity across all areas of catalysis.
Volume 2 Issue 2, February 2019
Desalination processes generally leave brine as a by-product, which is then discharged back into the environment. This Perspective looks at recent procedures for using this brine instead as resource for the production of hydrochloric acid and sodium hydroxide through direct electrosynthesis.
The ability to functionalize normally unreactive sites in molecules opens up tremendous flexibility in synthesis design and structural modification, in addition to reducing the need for multiple steps or highly reactive reagents. Now, a dual-catalytic strategy, demonstrated with the methods for the β-arylation of aliphatic alcohols and for the enantioselective γ-hydroarylation of allylic alcohols, is reported for such reactions.
Despite the many recent developments in iron-catalysed cross-couplings, the mechanistic understanding of these reactions is lacking compared to the more studied palladium and nickel variants. Here, the authors find that during iron-catalysed Negishi reactions the diphosphine ligand predominately binds to the zinc—rather than the iron—centre.
Identification of single-atom active sites in carbon-based cobalt catalysts during electrocatalytic hydrogen evolution
Carbon-based single-atom catalysts usually rely on nitrogen co-doping to stabilize the single metal atoms as metal–N4 moieties. Now, Wei, Yao and colleagues make use of operando techniques to show that under alkaline hydrogen evolution reaction conditions the Co–N4 active site undergoes structural distortion to a HO–Co–N2 configuration.
MOFs have found limited application in catalysis so far, as the result of their limited thermal and hydrolytic stability. Now, non-thermal plasma is shown to be able to promote and sustain the activity of HKUST-1 and other MOFs towards the water–gas shift reaction despite the presence of water. [In a previous version of the graphical abstract, CO conversion was incorrectly labelled CO2 conversion.]
Single-atom catalysts are receiving much attention, but insights into their active sites or the differences in reactivity with conventional nanoparticles are still controversial. Now, operando studies on CO oxidation with Ir/MgAl2O4 accompanied by computational investigations reveal important features of this class of catalyst.
Structural selectivity of supported Pd nanoparticles for catalytic NH3 oxidation resolved using combined operando spectroscopy
The selective catalytic oxidation of ammonia with palladium is an important reaction in the context of NOx abatement, although limited structural information about the catalyst under reaction conditions is available. Now, an operando study reveals the speciation of palladium and identifies crucial palladium–nitride species.
Catalytic hydrogen atom transfer from hydrosilanes to vinylarenes for hydrosilylation and polymerization
Hydrogen atom transfer processes are commonly encountered in chemical and biological systems. Here the authors report a redox-neutral hydrogen atom transfer through the activation of hydrosilanes with a Lewis base. Further, they demonstrate that this initial step can be directed towards hydrosilylation or polymerization depending on the choice of catalyst.