Recent advances in iridium-based catalysts with different dimensions for the acidic oxygen evolution reaction

Abstract

Proton exchange membrane (PEM) water electrolysis is considered a promising technology for green hydrogen production, and Iridium (Ir)-based catalysts are the best materials for anodic oxygen evolution reactions (OER) owing...

Enhanced Stability of Iridium Nanocatalysts via Exsolution for the CO2 Reforming of Methane

“…The choice of the perovskite oxide for this study was based on the lower temperatures required to achieve phase purity when using Ba as the A-site element, compared to the archetypal A-site (Sr, in SrTiO 3 ), which often also leads to segregation when sintered at the required higher temperatures to achieve a solid solution. , The lower calcination and sintering temperatures are also expected to result in smaller crystal grains, with the added benefit of possibly depleting the perovskite support of a higher amount of exsolvable metal (Ir), which is initially homogeneously distributed as a dopant in the bulk structure of the host. Our choice of Ir as the active metal was based on the fact that it has shown remarkable activity in several catalytic reactions even in low concentrations, which implies that our work is of impact to areas of application beyond the one demonstrated in this work . Nevertheless, iridium catalysts have been proven to be very effective in activating methane at low temperatures hence we believe it is an ideal choice for this study .…”

“…Our choice of Ir as the active metal was based on the fact that it has shown remarkable activity in several catalytic reactions even in low concentrations, which implies that our work is of impact to areas of application beyond the one demonstrated in this work. 38 Nevertheless, iridium catalysts have been proven to be very effective in activating methane at low temperatures hence we believe it is an ideal choice for this study. 39 Moreover, the choice of a perovskite oxide as support was made as perovskites have emerged as a promising class of support materials in heterogeneous catalysis due to their high thermal stability, structural features, and tunable nature.…”

Recent advances and perspectives of Ir-based anode catalysts in PEM water electrolysis

“…17,18 Specifically, the acidic environment severely limits the choice of materials for internal components that should be more corrosion-resistant. 19,20 In particular, it is urgent to develop more effective anode catalysts for oxygen evolution reactions (OER) that undergo harsh oxidation conditions. 21,22 The current electrodes that can be used as PEMWE anode catalysts mainly rely on iridium (Ir), ruthenium (Ru)-based, and other noble metal catalysts or their oxides.…”

Ir-Doped Bilayer Heterojunction Hollow Nanoboxes for Electrocatalytic Oxygen Evolution

“…On this account, by adopting ZIF-67 nanocubes as the template, we report a novel and efficient hollow heterobilayer catalyst doped with a low amount of Ir, Ir-ZIF-67@CoFe Prussian blue analogue (PBA) double-shell nanoboxes (DSNBs), which combines the advantages of a hollow structure and heterojunction. Moreover, heterogeneous interfaces can promote interfacial charge transfer between different components, thereby altering the valence state of the active site . In addition, profiting from the adjusted electronic structure and excellent synergy, Ir-ZIF-67@CoFe PBA DSNBs exhibit excellent electrocatalytic performance in 1 M KOH.…”

“…Moreover, heterogeneous interfaces can promote interfacial charge transfer between different components, thereby altering the valence state of the active site. 37 In addition, profiting from the adjusted electronic structure and excellent synergy, Ir-ZIF-67@CoFe PBA DSNBs exhibit excellent electrocatalytic performance in 1 M KOH. At 10 mA•cm −2 , only a mere overpotential of 269 mV and a small Tafel slope of 80.1 mV•dec −1 are required.…”