Going from Pt to PGM-free Catalysts: Effects of Ink Compositions on PEM Water Electrolysis.

The commercialisation of PEM water electrolysis is still hindered by the necessity of using noble metals that are rare, expensive and therefore unsustainable. To replace the benchmark HER catalyst Pt with more abundant materials, promising non-noble catalysts need to be identified and optimal electrode preparation and electrolysis conditions need to be transferred between catalyst materials to reveal their full potential under industrially relevant conditions. This study investigates the optimal ink composition for spray-coating the cathode regarding the effects on electrode structure, performance and catalyst layer composition.

A terpyridine-based copper complex for electrochemical reduction of nitrite to nitric oxide.

In biological systems, nitrite reductase enzymes (NIRs) are responsible for reduction of nitrite (NO) to nitric oxide (NO). These NIRs have mostly Cu- or Fe-containing active sites, surrounded by amine-containing ligands. Therefore, mononuclear Cu complexes with N-donor ligands are highly relevant in the development of NIR model systems and in the mechanistic investigation of the nitrite reduction reaction.

Rapid hydrolysis rates of thio- and phosphate esters constrain the origin of metabolism to cool, acidic to neutral environments.

Universal to all life is a reliance on energy carriers such as adenosine triphosphate (ATP) which connect energy-releasing reactions to energy-consuming processes. While ATP is ubiquitously used today, simpler molecules such as thioesters and polyphosphates are hypothesized to be primordial energy carriers. Investigating environmental constraints on the non-enzymatic emergence of metabolism, we find that hydrolysis rates-not hydrolysis energies-differentiate phosphate esters and thioesters.

Unlocking the Activity of Molecular Assemblies for CO Electroreduction in Zero-Gap Electrolysers via Catalyst Ink Engineering.

In recent years, CO electrolysis, particularly the electrochemical reduction of CO to CO in zero-gap systems, has gained significant attention. While Ag-coated gas diffusion electrodes are commonly used in state-of-the-art systems, heterogenized molecular catalysts like bis-coordinated homoleptic silver(I) N,N-bis(arylimino)-acenaphthene (Ag-BIAN) complexes are emerging as a promising alternative due to their tunability and high mass activity. In this study, the influence of ink composition on the performance of Ag-BIAN-based GDEs in zero-gap electrolyzers (ZGEs) are systematically explored at 60 °C and 600 mA cm⁻.

Insights into the Electrochemical CORR Performance and Binding of Small Molecules on Quaternary Thiospinels AgFeSnS and CuFeSnS.

Using a mechanical synthesis method in the form of ball milling and an additional annealing step, a novel and accelerated route for the synthesis of the thiospinels toyohaite (AgFeSnS) and rhodostannite (CuFeSnS) was discovered. Both thiospinels display faradaic efficiencies of up to 73% for CO reduction to CO using an organic electrolyte in an H-type cell. The materials were furthermore implemented in a zero-gap electrolyzer, with toyohaite producing 22% CO and 52% H at 100 mA cm and rhodostannite 28% CO and 37% H.

FeNiS-A Potent Bifunctional Efficient Electrocatalyst for the Overall Electrochemical Water Splitting in Alkaline Electrolyte.

For a carbon-neutral society, the production of hydrogen as a clean fuel through water electrolysis is currently of great interest. Since water electrolysis is a laborious energetic reaction, it requires high energy to maintain efficient and sustainable production of hydrogen. Catalytic electrodes can reduce the required energy and minimize production costs.

Electrochemically induced metal- vs. ligand-based redox changes in mackinawite: identification of a Fe- and polysulfide-containing intermediate.

Under anaerobic conditions, ferrous iron reacts with sulfide producing FeS, which can then undergo a temperature, redox potential, and pH dependent maturation process resulting in the formation of oxidized mineral phases, such as greigite or pyrite. A greater understanding of this maturation process holds promise for the development of iron-sulfide catalysts, which are known to promote diverse chemical reactions, such as H, CO and NO reduction processes. Hampering the full realization of the catalytic potential of FeS, however, is an incomplete knowledge of the molecular and redox processess ocurring between mineral and nanoparticulate phases.

Correction: Simultaneous synthesis of thioesters and iron-sulfur clusters in water: two universal components of energy metabolism.

Correction for 'Simultaneous synthesis of thioesters and iron-sulfur clusters in water: two universal components of energy metabolism' by Sebastian A. Sanden et al., Chem.

Simultaneous synthesis of thioesters and iron-sulfur clusters in water: two universal components of energy metabolism.

Thioesters are important intermediates in both synthetic organic and biosynthetic reaction pathways. Here we show that thioesters can be synthesized in an aqueous reaction between thioacetate and thiols. The reaction can be coupled to a second reaction between sulfide and either ferrous or ferric iron, which drives the reaction forward.