Li Cations Activate NiFeOOH for Oxygen Evolution in Sodium and Potassium Hydroxide.

The efficiency of electrolysis is reduced due to the sluggish oxygen evolution reaction (OER). Besides catalyst properties, electrocatalytic activity also depends on the interaction of the electrocatalyst with the electrolyte. Here, we show that the addition of small amounts of Li to Fe-free NaOH or KOH electrolytes activates NiFeOOH for the OER compared to single-cation electrolytes.

Overcoming Diffusion Limitation of Faradaic Processes: Property-Performance Relationships of 2D Conductive Metal-Organic Framework Cu (HHTP) for Reversible Lithium-Ion Storage.

Faradaic reactions including charge transfer are often accompanied with diffusion limitation inside the bulk. Conductive two-dimensional frameworks (2D MOFs) with a fast ion transport can combine both-charge transfer and fast diffusion inside their porous structure. To study remaining diffusion limitations caused by particle morphology, different synthesis routes of Cu-2,3,6,7,10,11-hexahydroxytriphenylene (Cu (HHTP) ), a copper-based 2D MOF, are used to obtain flake- and rod-like MOF particles.

Reversible and Irreversible Cation Intercalation in NiFeO Oxygen Evolution Catalysts in Alkaline Media.

For electrocatalysts with a layered structure, ion intercalation is a common phenomenon. Gaining reliable information about the intercalation of ions from the electrolyte is indispensable for a better understanding of the catalytic performance of these electrocatalysts. Here, we take a holistic approach for following intercalation processes by studying the dynamics of the catalyst, water molecules, and ions during intercalation using operando soft X-ray absorption spectroscopy (XAS).

Stabilization of a Mn-Co Oxide During Oxygen Evolution in Alkaline Media.

Improving the stability of electrocatalysts for the oxygen evolution reaction (OER) through materials design has received less attention than improving their catalytic activity. We explored the effects of Mn addition to a cobalt oxide for stabilizing the catalyst by comparing single phase CoO and (CoMn)O films electrodeposited in alkaline solution. The obtained disordered films were classified as layered oxides using X-ray absorption spectroscopy (XAS).

Stable Acidic Water Oxidation with a Cobalt-Iron-Lead Oxide Catalyst Operating via a Cobalt-Selective Self-Healing Mechanism.

The instability and expense of anodes for water electrolyzers with acidic electrolytes can be overcome through the implementation of a cobalt-iron-lead oxide electrocatalyst, [Co-Fe-Pb]O , that is self-healing in the presence of dissolved metal precursors. However, the latter requirement is pernicious for the membrane and especially the cathode half-reaction since Pb and Fe precursors poison the state-of-the-art platinum H evolving catalyst. To address this, we demonstrate the invariably stable operation of [Co-Fe-Pb]O in acidic solutions through a cobalt-selective self-healing mechanism without the addition of Pb and Fe and investigate the kinetics of the process.