Volume 4 Issue 1, January 2021

Despite over a century of research to understand heterogeneous electrocatalysis, the precise mechanisms of action remain poorly understood. Now, it is proposed that the oxygen evolution reaction on IrO_x is driven by changes in the redox state of the Ir–O active sites, rather than by changes in the interfacial electric field.

Atomically dispersed and nitrogen-coordinated single iron site catalysts hold great promise to replace platinum for proton-exchange membrane fuel cells, but they suffer from significant performance loss. Now, solving the conundrum to distinguish durable and non-durable FeN₄ active sites can guide high-performance catalyst design.

Electrochemical CO₂ conversion to hydrocarbons has increasingly improved with the development of better catalysts. Now, a copper catalyst modified with a polymer boosts the selectivity for ethylene production to 87%.

Fe–N–C materials are a promising alternative to platinum for catalysing the oxygen reduction reaction in acidic polymer fuel cells. Now, a ⁵⁷Fe Mössbauer study reveals that while these catalysts initially comprise two distinct FeN_x sites, a high-spin FeN₄C₁₂ and a low- or intermediate-spin FeN₄C₁₀, only the latter is durable in operating conditions.

Electrochemical conversion of CO₂ into value-added chemicals holds promise to enable the transition to carbon neutrality, but enhancing the selectivity toward a specific hydrocarbon product remains a challenging task. Now, the authors present a Cu–polyamine hybrid catalyst that achieves Faradaic efficiency of 87% for ethylene and full-cell energy efficiency of 50%.

The carboazidation of olefins represents an effective strategy to introduce both carbon and nitrogen substituents into hydrocarbons, but asymmetric versions of this reaction remain elusive. Now, an iron-catalysed asymmetric radical carboazidation is introduced that yields chiral halogenated organoazides in high enantiomeric ratios.

The rational design of efficient water oxidation electrocatalysts is paramount to the development of electrochemical devices. Now, a Co-TiO₂ single-site catalyst is presented for alkaline water oxidation with high intrinsic activity, and its mechanism has been studied by grand canonical quantum mechanics calculations and in situ techniques.

Obtaining spatially resolved spectroscopic information for catalysts under working conditions remains challenging. Here, an approach that combines X-ray absorption spectroscopy with microtomography is introduced and showcased for the selective catalytic reduction of NO_x with ammonia over a Cu-SSZ-13 washcoated monolith catalyst.

General methods to regioselectively introduce both amine and alcohol functionalities into alkene substrates to afford 1,2-aminoalcohols in a single step are lacking. Now, this has been addressed by a metal-free photosensitization strategy using oxime carbonate as a suitable bifunctional reagent.

Multi-element oxide catalysts can feature superior properties compared with their single-element analogues but obtaining such complex structures remains a challenge. Here, a method is reported to access single-phase denary nanoparticles as stable and efficient catalysts for the combustion of methane.

The coupling of aryl halides and arylboronic acids is generally performed by metal-catalysed Suzuki–Miyaura reactions while metal-free approaches remain elusive. Here an organocatalytic approach based on amine catalysts is introduced for the preparation of commercially relevant asymmetric biaryls.

The reactivity of transient carbocations provides interesting synthetic opportunities, but the selectivity control is challenging. Now, catalytic access to carbocation intermediates via metal-nitrenoid transfer into alkenes is reported and their regiocontrolled elimination is achieved, allowing the production of allylic lactams.