Atomically-resolved structural changes of ceramic supported nanoparticulate oxygen evolution reaction Ir catalyst

“Nano Lab” Advanced Characterization Platform for Studying Electrocatalytic Iridium Nanoparticles Dispersed on TiOxNy Supports Prepared on Ti Transmission Electron Microscopy Grids

“…The next constituent part of the Nano Lab is the unique electrochemical analysis enabled by the floating-type electrode setup, where the TEM grid serves as the WE (i.e., modified floating electrode setup�MFE). 28 Its main characteristic is that the active catalyst is placed on the surface of the electrolyte solution. Besides obtaining a well-resolved electrochemical signal, using this setup for the investigation of gasevolving reactions (i.e., OER) is beneficial as it also enables more efficient bubble management.…”

“…The next constituent part of the Nano Lab is the unique electrochemical analysis enabled by the floating-type electrode setup, where the TEM grid serves as the WE ( i.e. , modified floating electrode setupMFE) . Its main characteristic is that the active catalyst is placed on the surface of the electrolyte solution.…”

Supported Iridium‐based Oxygen Evolution Reaction Electrocatalysts ‐ Recent Developments

“…However, current state-of-the-art development of these techniques still does not enable one to investigate the behaviour of powdered samples, which correspond to supported Ir catalysts for OER. Nevertheless, insights into the structural changes of the catalyst, triggered by the electrochemical perturbation, can already be obtained with atomic resolution via the identical-location TEM approach, which is now generally well-established and has been employed for the study of supported electrocatalysts for OER [234,235] and ORR. [236] Most of the presented materials were leading to a decrease in iridium utilization, from 10 wt% to 70 wt%, with usually enhanced performances.…”

Catalyst Stability in Aqueous Electrochemistry

“…As previously stated, the adhesion of gaseous products on the catalyst's surface during gas-evolving reactions can result in activity losses due to limited reactant availability. 14,173,174 Physical methods, such as floating positioning of the electrodes, centrifugal acceleration, and ultrasonic assistance, that assist in the transport and release of gaseous product bubbles have been proposed. 174−176 Catalyst design for gasevolving electrocatalytic applications should also consider strategies to facilitate the detachment of gas bubbles from the electrode surface.…”

“…As previously stated, the adhesion of gaseous products on the catalyst’s surface during gas-evolving reactions can result in activity losses due to limited reactant availability. ,, Physical methods, such as floating positioning of the electrodes, centrifugal acceleration, and ultrasonic assistance, that assist in the transport and release of gaseous product bubbles have been proposed. − Catalyst design for gas-evolving electrocatalytic applications should also consider strategies to facilitate the detachment of gas bubbles from the electrode surface. Due to the fact that smaller bubbles have higher detachment frequencies, limiting bubble growth and coalescence by creating periodic confinement structures capable of guiding the bubble flow of the electrode surface (i.e., periodic cracks, striped-patterns, and three-dimensionally nanostructured catalysts) may provide greater accessibility to the active sites. ,− …”