Highly Selective Hydrogen Peroxide Production Using an AgPd-Based Electrocatalyst with Ultralow Pd Loading.

Efficient electrocatalysts are key to advancing H2O2 production via the oxygen reduction reaction (ORR), but challenges like high material costs and low efficiency hinder progress. Based on this, this study focuses on the development and evaluation of a bimetallic AgPd/C electrocatalyst with ultralow Pd loading (0.2 wt %) designed for the selective ORR, specifically targeting the production of H2O2. The catalyst was synthesized using a galvanic replacement method, combining Ag and Pd in a random atomic arrangement on Vulcan XC-72 carbon support to optimize the dispersion and conductivity of active sites. Electrochemical analyses revealed that the AgPd/C electrocatalyst exhibited remarkable selectivity for H2O2, maintaining selectivity above 75% within a defined potential range. This selectivity significantly outperformed the Vulcan XC-72 catalyst, which showed a notable decline over the same range. Furthermore, the AgPd/C catalyst displayed superior resistance to methanol crossover compared to commercial Pt/C electrocatalysts, demonstrating its potential for stable and efficient operation in methanol-fueled applications. The combination of Ag and Pd enhanced the selectivity for the two-electron ORR mechanism and reduced energy requirements for initiating electroreduction, making it a promising candidate for applications requiring high H2O2 selectivity, such as green chemical processes. Our findings suggest that the selective 2e- ORR behavior arises from the surficial structure achieved via the galvanic replacement synthesis with ultralow Pd content.