Volume 3 Issue 8, August 2020

Suppressing the degradation of polymer electrolyte membrane fuel cells due to anode side-reactions during repetitive cell start-up/shut-down remains a formidable challenge. Now, a phase transition material of WO₃ has been explored as a smart catalytic switch to enable highly selective electrocatalysis and improve fuel cell longevity.

Dual nickel/photoredox catalysis is a promising alternative for palladium-catalysed cross-couplings, but suffers from limitations. Now, the substrate scope and reproducibility of this method are improved by avoiding catalyst deactivation and strategies to achieve the latter are reported.

Achieving high enantioselective control in the hydrogenation of aliphatic ketones is a long-standing challenge. Now, the design of a spiro iridium catalyst with a narrow, crowded chiral pocket allows highly enantioselective hydrogenation of these compounds.

Tuning the structures of subnanometric metal clusters is challenging but can unlock unexpected catalytic properties. Here, the authors show that changing the composition of MFI zeolite-encapsulated PtSn subnanometric clusters by adding just a few tin atoms can lead to a remarkable stability enhancement in propane dehydrogenation.

The stability of polymer electrolyte membrane fuel cells is limited by the degradation of the cathode catalyst during repetitive start-up/shut-down events — a parasitic oxygen reduction reaction on the anode causes an instantaneous potential jump at the cathode. The issue is now addressed by selectively suppressing the oxygen reduction reaction on the anode by exploiting the metal–insulator transition behaviour of Pt/H_xWO₃ catalysts.

Unlike with inorganic photocatalysts, the facet-dependent reactivity of conjugated polymers remains elusive. Now, the authors provide molecular-level insights on the reactive facets of crystalline poly(triazine imide) intercalated with LiCl and achieve a remarkable improvement in its overall photocatalytic water splitting activity.

Isolating the role of water in aqueous reactions where it is directly involved as a reactant is equally important and challenging. Now, by confining water inside an organic liquid matrix, the authors observe the formation of aqueous-rich nanodomains and find that the reactivity of the system varies with their nanostructure.

The Sonogashira cross-coupling is a key strategy in modern synthesis for C–C bond formation and introduction of the versatile alkyne functionality into organic molecules. Now, a complementary method is reported based on the palladium-catalysed cross-coupling of lithium acetylides with aryl bromides.

The asymmetric O-alkylation of alcohols is a useful route to chiral ethers, but aliphatic secondary alcohols have proven to be difficult substrates. Here the authors report a method to achieve this by developing conditions to avoid the decomposition of the alkylating agent.