Benchmarking Perovskite Electrocatalysts’ OER Activity as Candidate Materials for Industrial Alkaline Water Electrolysis

The selection and evaluation of electrocatalysts as candidate materials for industrial alkaline water electrolysis is fundamental in the development of promising energy storage and sustainable fuels for future energy infrastructure. However, the oxygen evolution reaction (OER) activities of various electrocatalysts already reported in previous studies are not standardized. This work reports on the use of perovskite materials (LaFeO3, LaCoO3, LaNiO3, PrCoO3, Pr0.8Sr0.2CoO3, and Pr0.8Ba0.2CoO3) as OER electrocatalysts for alkaline water electrolysis. A facile co-precipitation technique with subsequent thermal annealing (at 700 °C in air) was performed. Industrial requirements and criteria (cost and ease of scaling up) were well-considered for the selection of the materials. The highest OER activity was observed in LaNiO3 among the La-based perovskites, and in Pr0.8Sr0.2CoO3 among the Pr-based perovskites. Moreover, the formation of double perovskites (Pr0.8Sr0.2CoO3 and Pr0.8Ba0.2CoO3) improved the OER activity of PrCoO3. This work highlights that the simple characterization and electrochemical tests performed are considered the initial step in evaluating candidate catalyst materials to be used for industrial alkaline water electrolysis.