Recent spectroscopic and computational studies concerning the oxygen evolution reaction over iridium oxides are reviewed to provide state-of-the-art understanding of its mechanism.

Water electrolysis driven by electrical power generated from renewable energy sources will play a pivotal role in future sustainable societies, which requires adaptation of various reaction conditions as well electrolyte identities. Regardless, the anodic half-reaction oxygen evolution (OER) is considered kinetic bottleneck. This study provides quantitative description OER kinetics based on rigorous microkinetic analyses including Tafel analysis, isotope effects and temperature dependence...

The green hydrogen economy is expected to play a crucial role in carbon neutrality, but industrial-scale water electrolysis requires improvements efficiency, operation costs, and capital costs before broad deployment. Electrolysis operates at high current density involves the substantial formation of gaseous products from electrode surfaces electrolyte, which may lead additional resistance resulting loss efficiency. A detailed clarification bubble departure phenomena against surface...

Hydrogen production from renewable energy and ubiquitous water has a potential to achieve sustainability, although current electrolyzers cannot compete economically with the fossil fuel-based technology. Here, we evaluate electrolysis at pH 7 that is milder than acidic alkaline counterparts may overcome this issue. The physicochemical properties of concentrated buffer electrolytes were assessed various temperatures molalities for quantitative determination losses associated mass-transport...

Seawater electrolysis is an attractive way for green hydrogen production; however, it faces challenges in efficiency loss because of the overpotentials oxygen evolution reaction (OER) and (HER), high concentration overpotential, ohmic potential (iR) drop. Here, our electrolyte engineering approach led to introduction a highly conductive Cl–-containing borate/carbonate mixed buffer electrolyte. At molar ratio 1.0, this has new apparent pKa (pKa,app) pH 9.8. While typical water system removes...

This study reports on the impact of identity and compositions buffer ions oxygen evolution reaction (OER) performance at a wide range pH levels using model IrOx electrocatalyst. Rigorous microkinetic analysis employing kinetic isotope effects, Tafel analysis, temperature dependence measurement was conducted to establish rate expression isolated from diffusion contribution solution resistance. It found that OER kinetics facile with OH- oxidation compared H2 O, results which were highlighted...

Water electrolysis with sustainable energy is a pivotal element in realizing carbon-neutral future. A closely stacked assembly has been implemented industrial applications to effectively minimize voltage loss through the electrolyte. Nevertheless, gas bubbles are vigorously and constantly formed during overall water electrolysis, particularly at high current densities. This study investigates bubble-induced resistance where interelectrode gap was minimized mimic practical device. At...

High current density reaching 1 A cm-2 for efficient oxygen evolution reaction (OER) was demonstrated by interactively optimizing electrolyte and electrode at non-extreme pH levels. Careful assessment revealed that the state-of-the-art nickel-iron oxide electrocatalyst in alkaline solution maintained its high OER performance with a small Tafel slope K-carbonate 10.5 353 K. The improved when Cu or Au introduced into FeOx -modified nanostructured Ni as third element during preparation of...

Near-neutral pH water electrolysis driven by renewable electricity can reduce the costs of clean hydrogen generation, but its low efficiency and gas crossover in industrially relevant conditions remain a challenge. Here, it was shown that electrolyte engineering could suppress dissolved gases such as O

Toward large-scale deployment of water electrolysis, non-extreme pH solution is a promising reaction medium because its mild condition can avoid the use expensive corrosion-tolerant materials in electrolyzer. In these electrolytes, however, electrocatalytic performance was lower than extreme counterparts. This study reports on oxidized copper and molybdenum species that catalyze hydrogen evolution (HER) carbonate buffer electrolytes. Electrocatalytic testing electrolyte revealed Cu addition...

Water electrolysis with sustainable energy is a pivotal element in realizing carbon neutral future. The industrial application has implemented closely stacked assembly to effectively minimize voltage loss through the electrolyte. Nevertheless, gas bubbles are vigorously and constantly formed during overall water electrolysis, particularly at high current densities. This study shed light on bubble-induced resistance assembly, whose interelectrode gap intentionally minimized mimic practical...

Water electrolysis driven by renewable electricity produces green hydrogen, which will play a pivotal role in realizing sustainable society. However, the production cost of hydrogen is currently $5.3/kg, nearly four times higher than $1.4/kg grey [1] necessitates reduction toward its large-scale deployment. While reducing electrolyzer one key interventions, [2] extremely acidic or alkaline conditions commercialized electrolyzers require expensive corrosion-tolerant materials as components,...

The Cover Feature shows large mass-transport flux made possible by the highly concentrated buffer solution at elevated temperatures for water splitting. demonstrated electrolysis performance in was comparable to that of conventional electrolyzer operating extreme pH levels, casting a new proposal solutions can be regarded as an alternative environment electrolysis. More information found Full Paper T. Naito et al.

Electrocatalytic processes driven by the renewable electricity will play a pivotal role to achieve sustainable in our society, whereby thermodynamically stable chemicals are converted into value-added products or energy carriers. For instance, water electrolysis produces green hydrogen, and carbon dioxide yields commodity such as ethylene monoxide. [1] These commonly share an anodic half-reaction of oxygen evolution reaction (OER) that requires large overpotentials due its slow kinetics,...

High current density reaching 1 A cm −2 for efficient oxygen evolution reaction (OER) is demonstrated by interactively optimizing electrolyte and electrode at non-extreme pH levels. Careful assessment revealed that the state-of-the-art nickel-iron oxide electrocatalyst in alkaline solution maintained its high OER performance with a small Tafel slope K-carbonate 10.5 353 K. The was improved when Cu or Au introduced into iron (FeO x ) as third element during preparation of electrodeposition....