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Our findings disclose that P-functionalization successfully enhances the oxygen evolution reaction (OER) activity of different cobalt-based catalysts (namely, La_0.2Sr_0.8CoO_3–δ, La_0.2Sr_0.8Co_0.8Fe_0.2O_3–δ, and CoO_x) at near-neutral pHs and that both phosphate ion assistance in the OER mechanism and catalyst Co oxidation state can play a role in the enhanced OER activity.

A vanadium redox flow battery (VRFB) is a grid-scale energy storage device. Its energy conversion unit consists of a cell stack that comprises ion-exchange membranes to separate positive and negative electrode. The projected lifetime of a VRFB is 20 years and 7’000 charge-discharge cycles. Lifetime tests of membranes under application relevant conditions are therefore impractical, and the development of an accelerated stress test (AST) to assess the chemical stability of membranes is crucial.

Perovskite oxynitride materials can act as effective photocatalysts for water splitting driven by visible light. A combined neutron and x-ray study now provides unique insight into the underlying processes at the solid–liquid interface and highlights how solar-to-hydrogen conversion can be improved.

The role of the oxygen stoichiometry of perovskite catalysts in the oxygen evolution reaction (OER) is systematically studied in the PrBaCo2O5+δ family. The reduced number of physical/chemical variables combined with in-depth characterizations such as neutron diffraction, O K-edge X-ray absorption spectroscopy(XAS), electron energy loss spectroscopy (EELS), magnetization and scanning transmission electron microscopy (STEM) studies, helps investigating the complex correlation between OER activity and a single perovskite property, such as the oxygen content. Larger amount of oxygen vacancies appears to facilitate the OER, possibly contributing to the mechanism involving the oxidation of lattice oxygen, i.e., the lattice oxygen evolution reaction (LOER). Furthermore, not only the number of vacancies but also their local arrangement in the perovskite lattice influences the OER activity, with a clear drop for the more stable, ordered stoichiometry.

The high operational and capital costs of polymer electrolyte water electrolysis technology originate from limited catalyst utilization and the use of thick membrane electrolytes. PSI researchers have developed novel multi-layer porous transport materials, which provide superior electrochemical performance in comparison to conventional single-layer structures.

The high operational expenditure of polymer electrolyte water electrolysis (PEWE) technology, dominated by kinetic losses from the sluggish oxygen evolution reaction (OER), inhibits large-scale market penetration. PSI researchers have developed a novel methodology to access underlying reaction mechanism of the OER. For the first time the reaction order for water has been determined. Advanced benchmarking of catalysts in technical environment also supports the development of novel, highly efficient catalyst materials.

Single atom catalysts hold great promise as O₂- or CO₂-reduction electrocatalysts, but a deeper understanding of their active sites’ structure and electronic properties is needed in order to render them sufficiently active and stable. To this end, we have used X-ray emission spectroscopy to determine these catalysts’ electronic configuration, and performed in situ measurements that unveil the effect of potential on this key feature.

Decarbonization of the energy system across different sectors using power-to-X concepts relies heavily on the availability of low-cost hydrogen produced from renewable power by water electrolysis. Polymer electrolyte water electrolysis (PEWE) is a promising technology for hydrogen (and oxygen) production for distributed as a well as centralized operation. The total cost of hydrogen is dominated by the electricity cost. Therefore, increase of conversion efficiency is pivotal in improving the commercial viability of electrolytically produced hydrogen. In this study, we investigate the prospects of improving conversion efficiency by reducing the membrane thickness from 200 to 50 micron and increasing the cell temperature from 60 to 120°C.

To improve the performance of single atom catalysts (SACs),  the structure of their active sites under operative conditions needs to be better understood. For this, we have performed in situ X-ray absorption spectroscopy measurements using a modulation excitation approach selectively sensitive to the species involved in the electrochemical reactions. This has allowed us to study the structural changes undergone by two types of SACs, and to tie the observed differences to their catalytic activities.

Evaluating potential electrolyte candidates is typically a lengthy procedure requiring long-term cycling experiments. To speed this process up, we have investigated potentiostatic lithium plating as a potential method for fast electrolyte suitability investigation. The applications of this methodology is not limited to liquid electrolytes, - effects of solid-state electrolytes, coatings, and other modifications can be readily assessed.