Volume 7 Issue 7, July 2024

Unravelling the key parameters that govern the activity of oxygen evolution reaction catalysts is an essential step towards efficient production of green hydrogen. Now, the repulsion between adsorbates on the electrocatalyst surface has been identified as a powerful promoter for the rate-limiting O–O coupling step.

Aqueous zinc-ion batteries are attractive due to their low cost, environmental friendliness, and exceptional performance, but the latter remains poorly understood. Now, a fast catalytic step involved in oxygen redox catalysis is shown to contribute to capacity at a high rate.

There is no doubt that identifying active sites at the atomic scale for designing optimal catalysts is a great challenge. Now, by combining computational and experimental results, an advanced methodology is proposed for understanding the structure–activity relationship at the atomic level.

Iridium oxide is the state-of-the-art catalyst for water oxidation in an acidic electrolyte. Now amorphous and crystalline iridium oxides are studied using operando time-resolved optical spectroscopy, together with other techniques, to reveal the nature and density of active centres and the role of adsorbate–adsorbate interactions.

Aqueous Zn-ion batteries are promising devices but their energy storage mechanism remains elusive. Now it is shown that these involve a catalytic mechanism based on water dissociation.

Electrocatalytic urea formation most commonly involves the co-reduction of NO_x species with CO₂. This limits overall energy efficiency as commodity-scale NO_x is produced from N₂ via NH₃. The swings in nitrogen oxidation state can be minimized through direct oxidative electrocatalytic reaction of CO and NH₃ to urea, as shown in this study.

Pt-based catalysts are the state of the art for the oxygen reduction reaction. Now the three-dimensional local atomic structure of PtNi and Mo-doped PtNi nanoparticles is revealed via atomic electron tomography, and a local environment descriptor of catalytic activity is put forwards.

CO₂ electroreduction is promoted by alkali cations in the electrolyte, but the precise mechanism by which this occurs is not clear. Now in situ infrared spectroscopy and ab initio molecular dynamics are combined to elucidate the specific role of alkali cations and their trends.

Pt-based catalysts are state-of-the-art cathodes in fuel cells, but they experience a trade-off between activity and durability. Now a Pt nanocatalyst with embedded cobalt oxide clusters is shown to promote stability during proton exchange membrane fuel cell operation without sacrificing activity, achieving 88.2% mass activity retention after 30,000 accelerated stress test cycles.

Understanding oscillation phenomena in catalysis is a long-standing challenge. Here the authors report a temporally and spatially resolved operando analysis of CO oxidation over Rh/Al₂O₃, revealing the interplay of Boudouard reaction and carbon combustion in generating the oscillations.

Cobalt, iron or manganese catalysts are the metals of choice in alkene functionalization reactions via catalytic metal hydride hydrogen atom transfer (MHAT). Now a complementary MHAT-like system based on copper is proposed to operate in a regioselective Markovnikov addition reaction of nucleophiles to olefins.

Mesoscopic mass transport is often ignored but it can influence electrocatalytic processes. This Analysis introduces a simple multi-scale model that couples diffusion to electrochemical surface kinetics and shows how mesoscopic mass transport determines product selectivity through catalyst morphology.