Oxygen reduction reaction electrolyte effect

In this chapter we review studies, primarily from our laboratory, of Pt and Pt-bimetallic nanoparticle electrocatalysts for the oxygen reduction reaction (ORR) and the electrochemical oxidation of H2 (HOR) and H2/CO mixtures in aqueous electrolytes at 274—333 K. We focus on the study of both the structure sensitivity of the reactions as gleaned from studies of the bulk (bi) metallic surfaces and the resultant crystallite size effect expected or observed when the catalyst is of nanoscale dimension. Physical characterization of the nanoparticles by high-resolution transmission electron microscopy (HRTEM) techniques is shown to be an essential tool for these studies. Comparison with well-characterized model surfaces have revealed only a few nanoparticle anomalies, although the number of bimetallics... 

Correlation of the effect of particle size on the oxygen reduction reaction has been reviewed extensively by Kinoshita [4,5], Stonehart [8], and Mukerjee [9]. The general consensus, based on a large number of steady-state polarization measurements in several electrolytes, is that ORR exhibits a strong particle size effect in the... 

Jin W, Du H, Zheng S, Xu H, Zhang Y. Comparison of the oxygen reduction reaction between NaOH and KOH solutions on a Pt electrode the electrolyte-dependent effect. J Phys Chem B 2010 114(19) 6542-8. 

Jung DH, Bae SJ, Kim SJ, Nahm KS, Kim P. Effect of the Pt precursor on the morphology and catalytic performance of Pt-impregnated on Pd/C for the oxygen reduction reaction in polymer electrolyte fuel cells. Int J Hydrogen Energy 2011 36(15) 9115-22. 

Nesselberger M, Ashton S, Meier JC, Katsounaros I, Mayrhofer KJJ, Arenz M (2011) The particle size effect on the oxygen reduction reaction activity of pt catalysts influence of electrolyte and relation to single crystal models. J Am Chem Soc 133(43) 17428-17433... 

Being thermally decomposed onto the surface of carbon, this complex is expected to form very small catalytically active NiCo204 spinel centers. Thus, we have studied the catalytic activity of the products of pyrolysis at different temperatures toward two electrochemical reactions -reduction of oxygen in alkaline electrolyte and intercalation of lithium into carbons in aprotic electrolyte of Li-ion battery. To our knowledge, the catalytic effect of the metal complexes in the second reaction was not yet considered in the literature. 

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