Effect of ordering of PtCu₃nanoparticle structure on the activity and stability for the oxygen reduction reaction

Abstract

In this study the performance enhancement effect of structural ordering for the oxygen reduction reaction (ORR) is systematically studied. Two samples of PtCu3 nanoparticles embedded on a graphitic carbon support are carefully prepared with identical initial composition, particle dispersion and size distribution, yet with different degrees of structural ordering. Thus we can eliminate all coinciding effects and unambiguously relate the improved activity of the ORR and more importantly the enhanced stability to the ordered nanostructure. Interestingly, the electrochemically induced morphological changes are common to both ordered and disordered samples. The observed effect could have a groundbreaking impact on the future directions in the rational design of active and stable platinum alloyed ORR catalysts.

Synthesis and Electrocatalytic Performance of Multi-Component Nanoporous PtRuCuW Alloy for Direct Methanol Fuel Cells

“…Figure 5a displays the CVs of the np-PtRuCuW and PtC catalysts in the N2-saturated 0.1 M HClO4 solution. Similar to our experiments at anode, the reduction peak of Pt oxides shows a slight positive shift for the np-PtRuCuW catalyst than that of PtC, indicating earlier onset of Pt-O(H) reduction [44,45]. The polarization results for the ORR on the np-PtRuCuW and PtC electrodes are shown in Figure 5b.…”

Durability of Unsupported Pt-Ni Aerogels in PEFC Cathodes

“…49 was partially related to the dissolution of ≈60% of its initial Ni-content. Moreover, previous works on Pt-Cu aerogels 50 and carbon-supported Pt-Cu and Pt-Ni electrocatalysts 49,51,52 have unveiled a correlation between the bulk phase non-noble metal content and the ORR activity that could explain this decrease of catalytic activity upon extended potential cycling.…”

Insights into electrochemical dealloying of Cu out of Au-doped Pt-alloy nanoparticles at the sub-nano-scale

“…In order to increase the PEM FC efficiency, Pt, as cathodic oxygen reduction reaction (ORR), is alloyed with less noble 3D metals like Co, Ni and Cu [1,[4][5][6][7][8][9][10][11][12]. Initial performances of Pt-alloys are already surpassing the US Department of Energy targets [1].…”

“…However, their stability is still under debate and is the topic of many current and future studies [13][14][15][16][17][18][19][20]. Three issues are foreseen for Ptalloys: (i) loss of initially superior ORR activity [13], (ii) formation of unstable porous nanoparticles [9,15] and (iii) poisoning of the PEM FC by the leached less noble metal cations [12,[21][22][23]. It is known that leached metals can cause the increase of the resistance of the polymer membrane and the lowering of the performance of the anode electrocatalysts due to the poisoning of the Pt surface [12,23].…”