An AI-guided laboratory search identified a palladium-oxide catalyst that kept its oxygen-evolution overpotential below 0.5 volts across acid tests totaling 1,000 operating hours. Researchers measured a catalyst-coated electrode in a three-electrode H-cell, a controlled bench-top cell rather than a working proton-exchange-membrane (PEM) electrolyzer, according to an arXiv preprint by Lila Sciences researchers.
The oxygen-evolution reaction (OER), which releases oxygen at an electrolyzer’s anode, is a difficult and durability-sensitive step in acidic water electrolysis. Current PEM systems rely heavily on iridium- or ruthenium-based oxides. Palladium is also a platinum-group metal, but the authors say its broader supply could ease some material constraints. The study does not measure equipment costs.
The team combined robotic experiments with machine-learning models and an adaptive search process, with people supervising parts of the workflow. It screened 2,942 catalysts across 53 material systems and 26 elements. The lead, called InMnPdOx, was 99.91 atom-percent palladium; indium and manganese together made up only 0.09 ± 0.02 percent, according to the authors’ composition measurement.
In durability tests, the researchers ran the catalyst in 1-molar sulfuric acid at room temperature and a current density of 10 milliamps per square centimeter. The test used repeated 12-hour operating blocks in a laboratory H-cell. InMnPdOx stayed below 0.5 volts of overpotential through 1,000 accumulated operating hours and retained 96 percent of its palladium.
Under the same study’s protocol, palladium oxide without the trace additives crossed that overpotential mark at about 200 hours; a second palladium-rich composition did so at about 470 hours. Overpotential is the extra voltage required for the reaction beyond its thermodynamic minimum, so the measurement reflects the catalyst’s contribution rather than the voltage or efficiency of a complete electrolyzer.
After operation, microscopy showed that InMnPdOx had developed a fine, needle-like surface structure. The authors associate that change with the catalyst’s stability and reduced palladium loss; it is a proposed explanation from this study, not yet a demonstrated design rule for other catalysts.
The reported current density and electrode configuration do not establish performance in a PEM stack, at commercial operating conditions, or over a full device lifetime. The paper is an arXiv preprint, and its authors are Lila Sciences employees; the paper also discloses that the company has filed or may file patents related to the materials, methods or platform.
Sources
- Ken J. Jenewein et al., “AI-guided high-throughput discovery of iridium- and ruthenium-free palladium-oxide catalysts for durable acidic oxygen evolution,” arXiv:2609.30133v1 (24 September 2026); full preprint PDF.
- Illustrative lead image: Hansjoachimkohnke via Wikimedia Commons, CC BY-SA 3.0. The image shows a generic electrochemical test cell, not the apparatus used in this study.
