Answers are grounded in this paper and cite their sources.
Dispersion determines platinum activity and selectivity The cover picture shows the change in the Pt specific activity towards the oxygen reduction reaction (ORR) on increasing the electrochemical surface area (ECSA). As E. Fabbri et al. present in their Full Paper on p. 1410 ff., the transition from extended layers to dispersed nanoparticles leads to an increase in the ECSA but a decrease in the specific ORR activity. The data of specific activity versus the ECSA follow a "master curve" obtained by comparing normalized Pt activities from different studies. The transition from dispersed Pt nanoparticles to extended layers also influences the Pt selectivity. At increased interparticle distance, a significant increase in the H2O2 production is also observed, which indicates the important role of a H2O2 as an intermediate in the ORR reaction on Pt nanoparticles.
No takes yet. Share an insight, caveat, or question.
Fabbri et al. (2014) studied this question.
Synapse has enriched 10 related papers. Consider them for comparative context: