News & Views

Development of an earth-abundant and inexpensive copper-based catalyst is desirable for CO₂ hydrogenation. Now, the combined application of a stable copper hydride and a Lewis pair is shown to effect activation of CO₂ as well as heterolysis of H₂, achieving significant turnover numbers.

Heterogeneous photocatalysts are rarely employed in industry for the synthesis of commodity chemicals due to efficiency problems. Now, a photochromic Bi₂WO_6–x/amorphous-BiOCl composite is reported, which features a remarkable activity for the photocatalytic oxidation of toluene into benzaldehyde and benzoic acid.

Artificial metalloenzymes generally consist of a synthetic (organo)metallic catalyst incorporated into a protein. Asymmetric catalysis by such metalloenzymes could result by virtue of the chiral protein environment. Now, redox-sensitive anchoring enables reversible incorporation of an iridium catalyst for transfer hydrogenation.

Typically, catalysts are discovered through trial and error coupled with chemical intuition. Now, an automatic machine-learning framework has been developed that can guide itself to find intermetallic surfaces with desired catalytic properties.

The chemical synthesis of natural products, such as sesquiterpenes, is a daunting task due to their complexity and precise functionalization, and multiple synthetic and purification steps that reduce overall yields are usually required. Now, a highly efficient alternative approach using supramolecular chemistry has been proposed by Tiefenbacher and co-workers.

Metalloprotein activity can be tuned by altering first- and second-sphere interactions with the metal ion or ions. Here, a non-canonical haem axial ligand is introduced into a myoglobin variant, modulating both. The resulting enhancement of cyclopropanation activity illustrates the utility of expanding the suite of available amino acids for biocatalyst engineering.

How the first metabolic network was organized to power a cell remains an enigma. Now, simple iron–sulfur peptides have been used to generate a pH-gradient across a protocell membrane by catalysing hydrogen peroxide reduction. This indicates that short peptides could have fulfilled the role of redox active metalloproteins in early life.

The identification of organic structure-directing agents capable of tailoring the physicochemical properties of microporous materials has remained a challenge. Now, a unique methodology to design organic mimics of reaction intermediates provides a route to optimize the selectivity of zeolite catalysts.

Control over the length and composition of polymers is key to controlling their properties. Now, a photoswitchable catalyst is shown to allow external control over reaction rates, chain lengths and even polymer composition in ring-opening polymerizations.

Pairing electrosynthetic anode and cathode processes (either convergent or divergent) is essential to maximize energy usage/sustainability and to minimize waste. New approaches to pairing in electrosynthesis are needed and the use of a palladium film membrane by Berlinguette and co-workers represents an effective paired reactor prototype that couples electrosynthesis with chemical catalysis.

Although the replacement of palladium with iron in metal-catalysed cross-couplings continues apace, the Suzuki synthesis of biaryls — arguably the most widely used class of such C–C bond formations — has remained elusive. Now, by use of a π-coordinating directing group, another step has been taken toward iron-catalysed Suzuki reactions.

Iron–sulfur metalloproteins are widespread and efficient catalysts for multielectron reduction of small molecules. Now, research shows that simple Fe₄S₄ cofactors and related complexes can perform effective reductive chemistry producing small hydrocarbons from CO₂ and CO.

The carboxylation of aromatic compounds with CO₂ is an attractive reaction, albeit limited in scope. Now, bulky ligands in a Rh(II) catalysed C–H carboxylation of 2-arylphenols are shown to override the standard ortho/para Kolbe–Schmitt-type regioselectivity allowing instead carboxylation at 2’.

Inexpensive, earth-abundant photoabsorbers for solar water splitting have, so far, not demonstrated notable performance. Now, voltage gained from a coaxial heterojunction coupled with nanostructure-enhanced photocurrent results in Cu₂O photocathodes demonstrating benchmark water-splitting performance.

The need for new single enantiomer drug substances helps drive the development of new asymmetric catalytic synthetic methods. A new enantioconvergent process enabled by an ionization racemization mechanism allows a hydrogenative route to chiral compounds with two stereocentres.

Reactive metal–support interactions are generally considered characteristic of oxide supports. Now, two-dimensional niobium carbide, a member of the MXenes family, has been used as a platinum support providing an active water-gas shift catalyst via reduction-induced formation of stable, catalytically active Nb–Pt nanoparticles.

Guiding principles for the design of novel catalysts are key to developing new synthesis approaches. Now, a general principle has been defined to predict the reactivity for the hydrogen cycle of atomically dispersed metals on carbon supports.

Discerning the precise mechanisms of photocatalytic energy conversion has long been a challenge. A computational multiscale approach reveals insights into the reaction pathways and rate-limiting steps of the oxygen evolution reaction, the bottleneck for water splitting on TiO₂ surfaces.

For electrocatalysts, the activity and stability is determined by the surface — often just a few atomic layers thick. Now atom probe tomography is used to examine the changing surface of an oxygen evolution catalyst at near-atomic-scale resolution, linking structure to activity and stability.

The solid electrolyte interphase that forms on graphite anodes plays a vital role in the performance of lithium-ion batteries. Now research shows that the formation of lithium fluoride deposits — one of the main components of the solid electrolyte interphase — is strongly influenced by the electrocatalytic activity of the anode.