Amorphous Ruthenium Oxide (RuOx) Coated Electrode for Electrolyzer, CECEARuO

Ruthenium Oxide (RuO2/RuOx) coated Titanium Felt (or carbon paper) is the "gold standard" anode for Proton Exchange Membrane (PEM) water electrolyzers. Unlike alkaline systems that can use nickel, PEM systems operate at a very low pH (acidic) and high potentials, where almost all other metals—except titanium and noble metals—would rapidly corrode.

Iridium is the only element that offers the required balance of high OER activity and extreme electrochemical stability in acid. (1) Performance: A typical RuOx-coated Ti felt electrode achieves 10 mA/cm2 at an overpotential of 220–280 mV in acidic media (0.5 H2SO4). (2) Loading: To balance cost and performance, industrial targets aim for "low loading" of around 0.5 - 2.0 mg/cm2 of Iridium.

Titanium/Nickel felt/mesh (also known as Titanium Fiber Paper) is the preferred Porous Transport Layer (PTL) for PEM anodes due to its unique physical properties: (1) Acid Stability: Titanium forms a stable, conductive passive oxide layer that prevents the bulk metal from dissolving in the acidic PEM environment. (2) Fiber Microstructure: The entangled titanium fibers provide much better electrical contact points for the catalyst layer than expanded metal mesh or sintered powder plates. (3) Porosity and Mass Transport: The high porosity (typically 60%–80%) allows water to reach the catalyst sites while simultaneously allowing oxygen bubbles to escape without causing "gas locking."

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

References: 

1. R. Boppella, et al. Strongly Coupled Metal/Amorphous Ru/RuOx Heterostructure for Efficient Electrocatalytic Hydrogen Production, ACS Catal., 2025, 15 (19): 16981–16991.
2. Z. Feng, et al. Boosting the OER via the metal–support interaction and H-bond network: amorphous RuOx on fluorinated Ruddlesden–Popper perovskites, Nanoscale (2026) 18 (22): 12041–12054.