Volume 4 Issue 6, June 2021

Electric current is now shown to induce movement of the atoms in electrocatalyst nanoparticles, leading to morphological changes and performance degradation. This electromigration effect needs to be taken into account when designing nanostructured catalysts for electrochemical devices.

Catalysts respond to reactive atmospheres, leading to intrinsically distinct active sites and reaction pathways in response to pressure changes. The degree of pressure gap depends on the nanostructure. Now, the gaps and discrepancies in in-situ and operando studies of CO₂-to-CH₃OH using CuZn catalysts have been rationalized.

Polyamines are a growing class of medically and agriculturally active biomolecules that have traditionally been difficult to source. Now, a bio-based platform for high-level production of diverse polyamines has been realized, showing the versatility of biocatalysis and the utility of conceptualizing metabolism as distinct modules.

The design of an original molecular architecture featuring an unusual sterically congested C(sp²)–C(sp³) stereogenic axis with six high rotational barriers results in the formation of six stereoisomers. The configuration of this axis can be controlled by transition metal catalysis and one stereoisomer can be produced selectively.

Identifying the active sites in supported catalysts comprising isolated metal atoms and subnanometric clusters is challenging because of the difficulty in obtaining detailed structural information under reaction conditions. Here, we discuss the limitations and pitfalls that may be encountered and provide suggestions accordingly.

Stereodivergent catalysis was previously limited to two possible states per stereogenic element. Now, it is demonstrated that stereoselective catalysis is capable of governing higher-order stereogenicity and the catalyst-controlled synthesis of four of the six possible stereoisomers arising from a single stereogenic unit is showcased.

Transition metal oxides constitute a promising class of catalysts for the oxygen reduction reaction, but they are found generally to be less active than Pt. Now, computational analyses and high-throughput experiments are used to understand the reasons behind the lower activity, and strategies to improve them are proposed.

Single-atom catalysts have become a frontier of heterogeneous catalysis, but to achieve a high stability under turnover is often a challenge. Now, a Pd/CeO₂ single-atom catalyst prepared using flame spray pyrolysis is able to stabilize the isolated Pd species during CO oxidation due to a high mobility of surface lattice oxygen.

The structural stability of electrocatalysts with complex nanoscale morphology, a requirement for their industrial implementation, often remains elusive. Now, a combination of electrical and electrochemical effects is shown to drive specific structural transformations of the catalyst during electrolysis.

Copper-zinc-alumina is used in industry to catalyse the synthesis of methanol from CO₂, but many aspects of its high performance remain elusive. Now, by using in situ and operando techniques over four orders of magnitude in pressure, the authors show how the catalyst structure and kinetics change with the applied conditions.

Structurally complex polyamines and polyamine analogues show potential as therapeutics and agrochemicals, but their production remains hampered. Here a polyamine yeast cell factory is developed that enables the gram-per-litre-scale titres of spermidine and the complete biosynthesis of a broad set of these compounds.

DYW domains catalyse cytidine deamination in plant RNA editing, but information on their structure and mode of action were lacking. Now, crystal structures of the DYW domain are reported and a gating domain, key catalytic residues and an unusual protein regulation mechanism are revealed.

Supported single-atom catalysts often feature a distinct reactivity when compared to traditional heterogeneous or homogeneous systems. Here the authors introduce a supported iridium single-atom catalyst for carbenoid O–H insertion characterized by a remarkable selectivity for aliphatic versus aromatic alcohols, unlike its homogeneous counterpart.