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

TL;DR

A new AgPd-based electrocatalyst with very low Pd content efficiently produces hydrogen peroxide with high selectivity.

Contribution

A bimetallic AgPd/C electrocatalyst with ultralow Pd loading is developed for selective hydrogen peroxide production.

Findings

The AgPd/C electrocatalyst showed over 75% H2O2 selectivity in a defined potential range.

The catalyst outperformed Vulcan XC-72 and showed superior resistance to methanol crossover.

The AgPd combination enhances two-electron ORR selectivity and reduces energy requirements.

Abstract

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.

Figures