News & Views in 2023

Elucidating the origin of light-induced reaction rate enhancement in plasmonic photocatalysis is very challenging. Now, bimetallic supercrystals are reported to boost photocatalytic hydrogen evolution from formic acid with the sole aid of intensified electric fields.

Iron–nitrogen–carbon (FeNC) catalysts are a viable alternative to platinum, but still lack the necessary performance. Now, pyrolysis under forming gas is found as a path to boosting their site density, activity and durability.

Enantioselective synthesis of chiral cyclobutanes via direct cycloaddition of C–C single bonds with C=C double bonds has remained an unmet challenge. Now, a photoelectrocatalytic system enabling asymmetric dehydrogenative [2+2] cycloaddition of alkyl ketones and alkenes has been developed.

With climate change concerns deepening, CO₂ fixation pathways to produce value-added chemicals are currently of interest. Now, synthetic biology and machine learning help developing such a pathway across modules that have been tested in vivo in Escherichia coli for the production of acetyl coenzyme A.

The search for novel biocatalysts for plastic degradation has recently become a hot topic. Now, multiple catalytic triads of well-known serine esterases were introduced into non-catalytic protein nanopores to enable the hydrolysis of PET nanoparticles.

Suppressing the formation of oxide encapsulation layers on the active metal during pretreatment would lead to increased catalytic activity in supported catalysts, but controlling the strong metal-support interactions is challenging. Now it is shown that cleverly introducing TiO_x patches onto Ru/MnO allows engineering effective oxide–oxide interface channels and avoids oxide overlayer formation, thus improving the performance of CO₂ hydrogenation to produce CO.

Diverse cytochrome P450s (CYPs) in nature can modify terpenoid scaffolds toward products with higher structural complexity and chemical diversity, but their discovery remains challenging. Now, an Escherichia coli -based gene screening platform enables high-throughput bacterial CYP screening, leading to efficient and diverse terpenoid biosynthesis.

A better understanding of the mechanism of electrochemical CO₂ reduction should enable development of electrocatalysts that are more active and selective. Now, through an isotopic labelling strategy, it has been discovered that there are at least two types of active sites on Cu electrocatalysts, one responsible for converting CO₂ to CO and another for further converting CO to useful C₂₊ products.

Selective electrochemical oxidation of ammonia provides an ideal pathway to synthesize hydrazine, but this process is outcompeted by a more favourable overoxidation to N₂. A molecular ruthenium catalyst has now flipped the script, circumventing the thermodynamic challenges to selectively generate hydrazine.

CRISPR-Cas9 is a major gene-editing tool that has attracted tremendous interdisciplinary efforts to ameliorate precise genome manipulation. Now, the pivotal structural features behind concerted double-stranded DNA cleavages by the Cas9 endonuclease have been captured through cryo-electron microscopy, laying the groundwork for improved Cas9 engineering.

The selective oxidation of methane to methanol using O₂ under mild conditions has been a challenge for decades. Now, this transformation is selectively achieved at ambient temperature with productivity as high as 67.4 μmol g_cat⁻¹ h⁻¹ on a reduced phosphomolybdate catalyst, where H₂ is required to keep the catalyst surface in a reduced state.

The electrochemical conversion of carbon dioxide to high-value multicarbon products is very desirable, but also fraught with immense complexity in process design. A twist in tuning product yields in this reaction could be based on water activity.

The electrochemical reduction of CO₂ in strong acids is difficult. Now a strategy utilizing immobilized cations significantly enhances system stability and efficiency, opening up avenues for optimized CO₂ conversion to C₂ products.

Enzymes are capable of controlling the reactivity and selectivity of catalytic mechanisms involving highly reactive intermediates. Now, flavine mononucleotide-dependent ene-reductases have been repurposed as photobiocatalysts for generating and taming unstable N-centred radicals, enabling their application in asymmetric radical C–N couplings.

Directed evolution has been extensively used to develop enzymes with enhanced properties, but there are limited examples of diverting key intermediates in catalytic cycles down alternative pathways. Now, a cytochrome P450 variant with promiscuous catalytic activity has been repurposed into a ketone synthase for the catalytic aerobic oxidation of internal alkenes to ketones.

Ethylene glycol is traditionally manufactured through energy-intensive thermocatalytic processes. Now, in a marked advance, a cascade catalytic system using electrochemically synthesized H₂O₂ for ethylene oxidation has been introduced. This strategy represents a benchmark for sustainable chemical manufacturing.

The chlor-alkali industry is one of the largest global electricity consumers. In the 1970s, the discovery of dimensionally stable anodes (DSAs) allowed for drastic savings in electricity consumption. The fundamental reasons behind the effectiveness of DSAs, however, were only clarified decades later.

The d-band model was proposed by Bjørk Hammer and Jens Nørskov almost 30 years ago to explain trends in the interaction of adsorbates with transition-metal surfaces. It remains a cornerstone in heterogeneous catalysis research and has inspired a wealth of later models.

Scientific research on human insulin was a crucial development in medicine, and its discovery led to the treatment of diabetes, one of the most prevalent global chronic diseases. A seminal work published in 1979 describing recombinant DNA technology to produce human insulin through biocatalysis has resulted in this field’s establishment and routine industrial applications.

The conditions employed for alkane dehydrogenation reactions are usually detrimental for catalyst stability. Now, subnanometre Pt clusters stabilized by the Ge-enriched double four-membered-ring units in a UTL-type zeolite structure show exceptionally high stability for this important transformation.