Reviews & Analysis

Controlling the stereochemical outcomes of chemical reactions is essential in modern chemical synthesis and manufacturing. Now, a nickel-catalysed, stereoselective hydrometalation and enantioconvergent alkyl–alkyl coupling of alkenyl boronic esters and α-bromo carbonyl derivatives has been achieved to provide single stereoisomers.

High current densities during CO₂ reduction in gas diffusion electrode (GDE) flow cells are incompatible with present online product-profiling methods. With the adaptation of proton-transfer reaction time-of-flight mass spectrometry, operando mechanistic information on C₁–C₄ product formation at copper-based GDEs is now accessible.

Hydrogen oxidation reactions in hydroxide exchange membrane fuel cells have slow kinetics. Switching from platinum group metal (PGM) electrocatalysts to those that are PGM-free is a challenging task as the latter are prone to oxidation. Now, stable and active nickel–molybdenum–niobium catalysts are introduced for this type of fuel cell.

Photosynthetic semiconductor biohybrids represent a viable approach to solar-to-chemical production but it remains challenging to tap their full potential. Now, a microbe–quantum dot hybrid has been developed for simultaneous fixation of CO₂ and N₂ with internal quantum efficiencies approaching the theoretical limits.

Artificial enzymes capable of catalysing significant transformations are highly desired but usually suffer from limitations in structural design and poor efficiency. Now, a monolayered metal–organic framework is reported as an editable biomimetic platform to achieve exceptional artificial photosynthesis performance.

The composition of an electrolyte has a significant effect on electrocatalytic reaction rates and product selectivities. One mechanism by which spectator alkali cations can dictate reaction kinetics is now better understood.

In the context of probing electrocatalytic systems, quartz crystal microbalance measurements, initially developed in 1959, provided the base for measuring mass changes at the electrode–electrolyte interface under reaction conditions.

Nuclear magnetic resonance (NMR) is a phenomenon at the heart of very important tools in analytical chemistry and medical diagnostics. Thirty-five years ago, Clifford Russell Bowers and Daniel Weitekamp developed the PASADENA experiment — an ingenious chemical scheme that boosts sensitivity of proton NMR by three orders of magnitude, widening the applicability of NMR altogether.

Sensitive and isomer-specific analytical tools detect elusive intermediates and reveal reaction mechanisms. Photoelectron photoion coincidence spectroscopy, introduced in 1966, now serves as a reaction microscope, identifies intermediates, and delineates gaseous and surface-confined processes in heterogeneous catalysis.

Understanding the molecular details of photoelectrochemical water oxidation is challenging. Now, theoretical and experimental evidence suggests that the accumulation of three adjacent holes is key to enabling the efficient oxidation of water to molecular oxygen on semiconducting oxides.

Stability is a key property for any catalyst. The description of stability, however, varies in the literature depending on the subfield. In this Review the authors present a systematic literature analysis aimed at identifying generalized deactivation modes and their prevalence in different areas of catalysis to offer a comprehensive descriptive framework of catalyst deactivation.

Metabolic engineering of microbes constitutes a promising strategy to make the industrial production of chemicals more sustainable. This Review discusses recent advances of targeted high-throughput genome editing to construct next-generation cell factories for bioproduction.

Single-atom, small cluster and nanoparticle catalysts feature intriguing reactivity for a variety of transformations, which is often attributed to the properties of specific atomic species. This Review critically revisits the reactivity of such catalysts in term of the ensemble effects that arise from the interaction of multiple metal atoms or single atomic species with neighbouring atoms from supports, additives or surface ligands.

Constraining metabolic models by enzyme capacities greatly improves genotype–phenotype predictions. Now, a method for estimating enzyme turnovers based on deep learning has been developed and used to reconstruct enzyme-constrained genome-scale metabolic models for more than 300 yeast species.

General catalytic methods for free radical-mediated asymmetric transformations have long eluded synthetic organic chemists. Now, NAD(P)H-dependent ketoreductases are repurposed and engineered as highly efficient photoenzymes to catalyse asymmetric radical C–C couplings.

Elucidating the reaction mechanism of a catalytic process is very challenging. Now, advanced solid-state nuclear magnetic resonance experiments demonstrate the importance of oxygenates to regulate the conversion of synthesis gas over an oxide–zeolite-based bifunctional catalyst material.

Rationalizing the difference in the catalytic properties within a group of materials is a challenging task. A method is now proposed that addresses this issue by predicting the activity and stability of platinum-based electrocatalysts from operando spectroscopic data.

The direct use of ammonia for asymmetric synthesis is highly sought after. Now, an efficient enantioselective carbene insertion into the N–H bond of ammonia has been developed, producing diverse valuable chiral α-amino acids.

Supported subnanometre catalysts are atom efficient and possess unique properties, but their structure–activity relations are not well understood. Now it is possible to reveal their structure sensitivity by combining multimodal experiments and computations.

The oxygen reduction reaction (ORR) plays a central role in electrochemistry for applications such as energy conversion and storage. This Review focuses on the fundamentals, technology and perspectives of ORR as an abiotic or biotic process at near neutral pH.