Bubble evolution and transport in PEM water electrolysis: Mechanism, impact, and management

Nanoporous PdIr alloy for high-efficiency and durable water splitting in acidic media

“…7,8 Alternatively, proton exchange membrane water electrolysis (PEMWE) technology, operated under acidic conditions, is a highly promising scheme for the production of renewable and clean hydrogen fuel because of its high current density, high-pressure operation, and fast hydrogen evolution reaction at the cathode. 9 Unfortunately, sluggish reaction kinetics accompanying the cathodic hydrogen evolution reaction (HER) and the anodic oxygen evolution reaction (OER) result in high overpotentials, greatly reducing the efficiency of H 2 production and hindering the progress of the PEMWE electrolyzers. 9,10 Furthermore, the harsh environment, with high local acidity and oxidative operation voltages, can lead to fast corrosion of the OER catalysts, rendering feasible the use of only a few noble-metal electrocatalysts.…”

“…9 Unfortunately, sluggish reaction kinetics accompanying the cathodic hydrogen evolution reaction (HER) and the anodic oxygen evolution reaction (OER) result in high overpotentials, greatly reducing the efficiency of H 2 production and hindering the progress of the PEMWE electrolyzers. 9,10 Furthermore, the harsh environment, with high local acidity and oxidative operation voltages, can lead to fast corrosion of the OER catalysts, rendering feasible the use of only a few noble-metal electrocatalysts. 11–13 Currently, Ir-based catalysts are the only available acidic OER electrocatalysts with both reasonable activity and stability for commercial PEMWE electrolyzers.…”

Nonprecious High‐Entropy Chalcogenide Glasses‐Based Electrocatalysts for Efficient and Stable Acidic Oxygen Evolution Reaction in Proton Exchange Membrane Water Electrolysis

“…Among different OER reaction conditions, acidic OER electrocatalysis has become crucially important for practical industrial applications compared to the process in neutral and alkaline conditions because of the diversified advantages of proton-exchange membrane water electrolyzers (PEMWEs) operating in acidic media over alkaline water electrolyzers, including excellent proton conductivity resulting in low ohmic resistance and high current density, long-term electrochemical stability, and much smaller gas crossover, as well as more compact system design. [6,7] Thus, developing highly efficient electrocatalysts under acidic conditions is imperative for the successful large-scale production of hydrogen energy beyond the laboratory scale.…”

Two‐Dimensional Amorphous Iridium Oxide for Acidic Oxygen Evolution Reaction

“…[13][14][15] Moreover, the wide application of acid proton exchange membranes (PEM) makes it more important to develop high-performance acid OER catalysts, because they have a direct impact on the feasibility of industry. [16][17][18] At present, only iridium (Ir)-based and ruthenium (Ru)-based catalysts exhibit good OER performance under acidic conditions. [19][20][21] Although the OER activity of Ru-based catalysts is slightly higher than that of Ir-based catalysts, their stability is lower than that of Ir-based catalysts.…”

“…* + O 2 + (H + + e À ). Specifically, for the intrinsic 1TÀ IrO 2 (11)(12)(13)(14)(15)(16)(17)(18)(19)(20) surface with an overpotential of 0.46 V, the AmÀ IrO 2 À Odv facilitates the weak adsorption of the OER intermediates and decreases the overpotential into 0.39 V. Meanwhile, both Osv and Odv facilitate improving the OER performance with lower overpotentials of 0.60 V and 0.64 V than the pristine (10-10) surface (0.68 V). For comparison, we also considered the lattice oxygen mechanism (LOM) and found that it is not energetically favorable in Table S3.…”