Articles

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.

For practical applications, water-oxidation catalysts should be inexpensive, active and stable. Here, Cronin and co-workers dope molybdenum into the Weakley sandwich-type polyoxometalate, showing that this dramatically lowers the overpotential for the oxygen evolution reaction while maintaining the stability against oxidation.

Selective catalytic reduction is employed at the exhaust of diesel vehicles to abate nitrogen oxide emissions. Now, guided by time-resolved X-ray absorption spectroscopy and transient experiments using Cu-SSZ-13 as the catalyst, the authors unravel important features of the reaction mechanism that allow the performance of the catalyst to be improved.

Single-atom catalysts are of growing importance, but the nature of their structure and reactivity remains under debate. Here, Sykes and co-workers show that single Pt atoms on a well-defined Cu₂O surface are capable of performing low-temperature CO oxidation, and provide data on the binding site and electronic structure of the Pt atoms.

Small metal nanoclusters often display high catalytic activity, but also low stability due to aggregation. Here, Xu and co-workers show that subnanometre Pd clusters can be contained within porous organic cages. Not only do the particles retain high catalytic activity, they also show excellent solubility and stability.

The choice of solvent system has important implications regarding the catalytic upgrading of carbohydrate-containing biomass. Here, Dumesic and co-workers study solvation effects in organic solvent/water mixtures and employ the obtained information to control the rate and selectivity of the acid-catalysed dehydration of fructose.

While methods for arylation of amines are well established, alkylation is a less well-developed process. Here, Hu and co-workers report amine alkylation using redox-active esters, using a combination of photoredox catalysis to generate the active electrophile and copper catalysis for the cross-coupling.

Zeolite-catalysed alkylations of phenolic compounds offer unique possibilities for the valorization of renewable aromatics into substituted arenes. Now, a mechanistic study reveals that the course of the reaction can be dramatically altered by changing the polarity of the solvent, which affects the nature of surface species and the pathway for the generation of the alkylating electrophile.

Understanding structure sensitivity—how the structural morphology of a surface influences a catalytic reaction—is important for rational catalyst design. Here, the synthesis and in-depth characterization of a range of size-defined nickel clusters shows the structure sensitivity of CO₂ hydrogenation, and also identifies two size-dependent reaction pathways.

Nanoconfinement effects are crucial in any process that involves porous materials. Here, the authors present a nanoporous catalyst platform that enables these effects to be studied in situ at the single-molecule and single-particle level with turnover resolution.

Ammonia synthesis is an energy-intensive process due to the high activation barrier for N₂ dissociation. Here, Hosono and co-workers show that the intermetallic compound LaCoSi can lower the energy requirement for N₂ activation and shift the rate-determining step of the process to NH _x formation under mild conditions.