Testing the Test: A Comparative Look at Catalyst Evaluation Techniques

Hydrogen Peroxide (H₂O₂) is a valuable oxidant with growing demand across industries for sustainable and on-site production. Electrocatalytic synthesis via the two-electron Oxygen Reduction Reaction (2e⁻ ORR) offers a cleaner alternative to the conventional anthraquinone process. This study evaluates the performance of a Gas Diffusion Electrode (GDE) setup for H₂O₂ electrosynthesis by benchmarking it against the well-established Rotating Ring-Disk Electrode (RRDE) technique.

Four catalysts; Vulcan, Pd/C, and their Benzoquinone (BQ)-modified counterparts, were investigated in Alkaline media (1 M KOH). RRDE measurements were used to assess H₂O₂ Selectivity and ORR Activity through disk/ring current analysis and Tafel slopes. These results were then compared to the performance of the same catalysts in a GDE configuration, where H₂O₂ Selectivity was measured. The comparison provides insight into the scalability and reliability of GDEs for practical H₂O₂ production.