Amorphous Platinum-Iridium-Ruthenium-Oxide (PtIrRuOx, Atomic Ratio=1:2:2) Coated Electrode for Electrolyzer, CECEAPtIrRuO

Amorphous Platinum-Iridium-Ruthenium-Oxide (Pt-Ir-Ru-Ox or PtIrRuOx) coated electrodes represent an advanced class of multi-metallic, non-crystalline catalysts designed for demanding water electrolysis, unitized regenerative fuel cells (URFCs), and harsh chemical processing. By engineering a quaternary system that combines the catalytic strengths of three precious metals (Pt, Ir, Ru) into an amorphous matrix, this material overcomes the trade-offs between catalytic activity, electronic conductivity, and long-term durability typical of single- or binary-oxide systems.

Each element serves a targeted role within the amorphous oxide network: (1) Ruthenium (Ru): The kinetic workhorse for the Oxygen Evolution Reaction (OER). It exhibits the lowest intrinsic activation barrier for splitting water in acid, but pure RuO2 suffers from rapid dissolution under high anodic potentials. (2) Iridium (Ir): The primary stabilizer. It forms a corrosion-resistant IrOx framework that locks Ru active sites into place, preventing hyper-oxidation to soluble species (RuO4). (3) Platinum (Pt): Enhances bulk electronic conductivity across the oxide coating. In unitized regenerative devices, it acts as the primary catalyst for the Oxygen Reduction Reaction (ORR) and Hydrogen Evolution Reaction (HER). 

Unlike crystalline Rutile-type oxides (IrO2, RuO2), the long-range disordered structure of an amorphous film provides distinct electrochemical benefits: (1) Abundant High-Energy Active Sites: Amorphous materials lack long-range crystal lattices, creating a high concentration of structural defects, dangling bonds, distorted metal-oxygen coordination sites, and oxygen vacancies. This maximizes the electrochemically active surface area (ECSA). (2) Suppression of Lattice Oxygen Mechanism (LOM): Rapid dissolution in crystalline Ru/Ir oxides often proceeds via the LOM, where oxygen atoms from the crystal lattice are leached out. Amorphous arrangements favor the Adsorbate Evolution Mechanism (AEM), suppressing structural degradation and structural collapse during OER. (3) Flexible Lattice & Corrosion Resistance: The absence of grain boundaries prevents localized intergranular corrosion, preventing acid electrolyte ingress down to the underlying Titanium/Niobium substrate.

Notes: Please try to store the PtIrRuOx electrodes in a dry place.

References: 

1. S. Siracusano, et al. Nanosized IrOx and IrRuOx electrocatalysts for the O2 evolution reaction in PEM water electrolysers, Appl. Catal. B Environ.. 2015, 164, 488-495.
2. E. Sadeghi, et al. Shaping low-iridium IrRuOx electrocatalysts with structural and electronic modulation for proton exchange membrane electrolyzers,  J. Mater. Chem. A, 2025,13, 39841-39858.