Probing the Pt Surface for Oxygen Reduction by Insertion of Ag

Abstract

We report on the probing of the Pt surface for oxygen reduction reaction (ORR) by insertion of Ag. Therefore, PtAg bimetallic nanoparticles were prepared by pulse electrodeposition. In a second step, Ag was electro-dissolved in acidic media from the particles under formation of Pt skeleton. The ORR activity of these Pt skeleton depends on two factors: (1) on the surface properties of the Pt-shell and (2) on the electronic as well as geometric influences of the remaining Ag in the particle core. By varying the conditioning procedure prior to measuring the ORR activity, we were able to differentiate between these two effects.

Methanol Oxidation Reaction Performance on Graphene‐Supported PtAg Alloy Nanocatalyst: Contrastive Study of Electronic and Geometric Effects Induced from Ag Doping

“…[15][16][17][18] Recently, some studies have also focused on the microstructure of PtAg alloy on the electrocatalytic performance. [19][20][21][22][23] To the best of our knowledge, little study has been devoted to contrastively investigating the influences of electronic and geometric effects on the PtAg alloy electrocatalytic performance towards MOR.…”

“…In previous study, Pt electronic modification induced by Ag incorporation was emphasized to explain the enhanced electrocatalytic activity, stability and durability . Recently, some studies have also focused on the microstructure of PtAg alloy on the electrocatalytic performance . To the best of our knowledge, little study has been devoted to contrastively investigating the influences of electronic and geometric effects on the PtAg alloy electrocatalytic performance towards MOR.…”

Activation/Inhibition Effects during the Coelectrodeposition of PtAg Nanoparticles: Application for ORR in Alkaline Media

“…[20] The mechanism of formation of the PtAg nanoparticle resulting in the growth of an alloyed PtAg core surrounded by a Agenriched shell is elucidated. The PtAg nanoparticles exhibit higher ORR activity as compared with pure Ag in 1 m KOH, and thus may be a candidate for ORR catalysts in, for example, alkaline fuel cells.…”

Synthesis of hollow PtAg alloy nanospheres with excellent electrocatalytic performances towards methanol and formic acid oxidations

“…It is proposed that the incorporation of Ag increases the 5d-orbitals vacancy of Pt, reducing back-donation of 5d electrons to CO, and thus weakening the interaction between Pt and CO ads and enhancing the electrocatalytic capability. 36,[45][46][47] To study the electrocatalytic stability of the PtAg alloy and Pt black towards the oxidations of methanol and formic acid, chronoamperometric tests were conducted for 1600 s under room temperature and the results are shown in Fig. 7(d and e).…”

“…It suggests that the electron transfer from Pt to Ag related to electronic interaction between Ag and Pt and further conrms the formation of PtAg alloy. 27,36,37 The electrocatalytic activity of the PtAg alloy was characterized by CV as shown in Fig. 7(a).…”