Articles

Catalytic arene carboxylation with CO₂ is a challenging reaction, with limited substrate scope and selectivity. Now, a redox neutral method based on a ligand-assisted Rh-catalysed C–H activation is shown, which features broad scope and provides access to important and biologically relevant structural motifs

Alcohols serve as versatile intermediates for the synthesis of pharmaceuticals and other valuable compounds. Here, Contente and Paradisi developed self-sustainable biocatalytic flow systems for the conversion of amines into various non-commercially-available and high-value alcohols.

The Fe protein of nitrogenase contains a redox-active [Fe₄S₄] cluster that plays a key role in electron transfer and substrate reduction. Here, Hu and co-workers show that the Fe protein of Methanosarcina acetivorans can reduce CO₂ and CO to hydrocarbons under ambient conditions.

Dynamic kinetic resolution (DKR) allows the conversion of both enantiomers of a racemic mixture into a single enantiomer of product, and requires both a stereoselective reaction and a means of rapidly racemizing the starting materials. Here, a highly stereoselective iridium-catalysed DKR of secondary allylic alcohols is reported, with mechanistic studies implying that substrate racemization is achieved through carbon–oxygen bond cleavage.

The generation of hydrogen fuel from water and visible light requires photoelectrodes that are inexpensive, stable and highly active. Now, Luo, Grätzel and co-workers report Cu₂O photocathodes that reach these goals. Incorporation into an unassisted solar water splitting device gives ~3% solar-to-hydrogen conversion efficiency.

The structural modification of inactive materials to effectively engineer active catalysts is very attractive. Here, layered crystalline Pd₃P₂S₈ is transformed by electrochemical lithiation into amorphous Li-incorporated nanodots. This process turns the inert parent material into a highly active and stable hydrogen-evolving catalyst.

Catalytic oxybromination is an important strategy for the upgrade of methane. Here, Pérez-Ramírez and co-workers employ operando photoelectron photoion coincidence spectroscopy as well as kinetic analyses and molecular simulations to unravel the complex reaction mechanism.

Methane borylation allows for the functionalization of an otherwise unreactive compound, enabling its use as a one-carbon building block; however, competing diborylation presents a selectivity issue. Now, a metal–organic-framework-based catalyst highly selective for monoborylation is reported. The selectivity is due to the reaction taking place within the catalyst pores, which excludes the formation of the larger diborlyated product.

Reactive metal–support interactions can tune the activity of heterogeneous catalysts, but have mainly been reported for oxide supports. Now, the metal–support interaction of platinum with MXenes at moderate temperature is reported, using the water-gas shift reaction as an example to showcase the properties of a representative catalyst.

Access to renewable hydrogen represents an important target for the success of the hydrogen economy. Now, a one-pot method is presented for the conversion of cellulosic biomass into hydrogen via formic acid as the intermediate, followed by its application to a fuel cell.

Energy-based descriptors have proven very successful in recent years despite their impracticality from an experimental viewpoint. Here, a universal descriptor based only on electronegativities and coordination numbers is put forward to predict the activity of carbon-based single-metal-atom catalysts for three of the most important electrocatalytic reactions. This descriptor can be extended to metal–macrocycle complexes with similar coordination environments.

The main hurdle to the deployment of carbon nanotubes in the electronics industry is the requirement of obtaining pure semiconductor nanotube horizontal arrays. Here, a method is presented to prepare highly pure semiconductor nanotubes by switching the direction of an applied electric field during synthesis.

A high reaction barrier is often assumed as the limiting factor in photocatalytic oxygen evolution reactions on titanium dioxide. Now, it is shown that the hole concentration at the semiconductor’s surface is the actual bottleneck in determining the catalytic efficiency.

Scaling relationships provide powerful predictive opportunities in catalysis, but at the same time also reflect the limitations related to the design of new catalytic systems. Now, theoretical studies show how mechanical strain on catalyst surfaces can be engineered to break scaling relations.

The creation of artificial reaction networks whose dynamics are programmable and predictable is a central goal in synthetic biology. This work describes an enzymatic reaction network that can generate tunable complex dynamics based on delayed and self-adapting substrate competition.

Despite the central role that the solid electrolyte interphase plays on the efficiency of Li-ion batteries, little is known about its formation mechanism. It is now shown that LiF forms on graphite anodes as a result of the electrocatalytic transformation of HF impurities present in the electrolyte.

Plasma catalysis holds promise for overcoming the limitations of conventional catalysis. Now, a kinetic model for ammonia synthesis is reported to predict optimal catalysts for use with plasmas. Reactor measurements at near-ambient conditions confirm the predicted catalytic rates, which are similar to those obtained in the Haber–Bosch process.

Morphological changes in catalyst structure are known to occur during electrocatalysis, and understanding such changes is important to gain insight into the catalytic process. Now, in the case of iridium oxide, these surface changes are probed in atomic-scale detail during the oxygen evolution reaction, and correlated with activity and stability.

Electrochemical routes for the production of hydrogen peroxide would reduce the waste inherent in the current anthraquinone process, and also make distributed and on-site production more feasible. Here, inexpensive reduced graphene oxide is proven to be a stable and selective catalyst for oxygen reduction at remarkably low overpotentials.

Aminocarboxylic acids are used in a broad range of domestic products and industrial applications. Here, Poelarends and co-workers report a chemoenzymatic route for the asymmetric synthesis of the antibiotic co-drug candidate aspergillomarasmine A and related aminocarboxylic acids by exploiting the broad substrate promiscuity of ethylenediamine-N,N′-disuccinic acid (EDDS) lyase.