Effect of Pd on the Electrocatalytic Activity of Pt towards Oxidation of Ethanol in Alkaline Solutions

Abstract

The understanding of electrocatalytic activity and poisoning resistance properties of Pt and Pd nanoparticles, recognized as the best electrocatalysts for the ethanol oxidation reaction, is an essential step for the commercialization of direct ethanol fuel cells (DEFCs). In this paper, mono and bimetallic Pt and Pd nanoparticles with different atomic ratios have been synthesized to study their electrocatalytic properties for an ethanol oxidation reaction in alkaline solutions. The different nanoparticles were physiochemically characterized by transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The electrochemical characterization was performed by cyclic voltammetry and chronoamperometry measurements. The electrochemical measurements indicate that Pt nanoparticles have much higher electrocatalytic activity for ethanol oxidation than Pd nanoparticles. The studies with bimetallic PtPd nanoparticles showed a significant impact of their composition on the ethanol oxidation. Thus, the highest electrocatalytic activity and poisoning resistance properties were obtained for Pt3Pd2 nanoparticles. Moreover, this study demonstrates that the poisoning of the catalyst surface through ethanol oxidation is related to the prevalence of the acetaldehyde–acetate route and the polymerization of acetaldehyde through aldol condensation in the alkaline media.

Characterization and Electrocatalytic Features of PtPd and PdPt Bimetallic Nanoparticles for Methanol Electro‐oxidation

“…This potential shift has been linked to forming the oxygen‐containing species and oxide coverage [38,39] . Thus, this observation reveals a lower tendency towards surface oxidation for Pt than for Pd [40] …”

“…X‐ray diffraction (XRD) measurements were carried out to determine the crystallographic structure of bimetallic nanoparticles (BNPs). XRD patterns of PtPd and PdPt BNPs showed the same appearance and shape due to the slight difference between the lattice parameter of Pt and Pd structures [22–24] . Figure S1 shows the XRD patterns of the prepared Pt and PtPd bimetallic nanoparticles, indexed with the face‐centered cubic (fcc) structure of Pt (JCPDF 04‐0802).…”

An Electrochemical Sensor for the Detection of Albendazole Using Glassy Carbon Electrode Modified with Platinum-Palladium Nanocomposites

“…The reported enhancement in the oxidation current could be attributed to the conductive nature and to the high surface area of the modifier, which enhances the charge transfer rate across the electrode–electrolyte interface when compared to its bare counterpart. The insertion of Pd to Pt catalysts enhances their catalytic activity, since the insertion process increases the catalyst surface area, reduces platinum poisoning, and resists variation in the bimetallic catalyst in acidic media [ 40 ]. In addition, palladium is much less expensive than platinum; therefore, the addition of palladium is of economic significance.…”

Ethanol Electrooxidation on Nickel Foam Arrayed with Templated PdSn; From Catalyst Fabrication to Electrooxidation Dominance Route

“…(3)]. However, the breakage of C−C bonds is hard so the most electrocatalysts derive incomplete ethanol oxidation reaction to C2 pathway [3–6] $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr {{\rm C}}_{2}{{\rm H}}_{5}{\rm O}{\rm H}\to {\rm C}{{\rm H}}_{3}{\rm C}{\rm H}{\rm O}+2{{\rm H}}^{+}+2{{\rm e}}^{-}\hfill\cr}}$$$ $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr {{\rm C}}_{2}{{\rm H}}_{5}{\rm O}{\rm H}+{{\rm H}}_{2}{\rm O}\to {\rm C}{{\rm H}}_{3}{\rm C}{\rm O}{\rm O}{\rm H}+4{{\rm H}}^{+}+4{{\rm e}}^{-}\hfill\cr}}$$$ $$$\vcenter{\openup.5em\halign{$\displaystyle{#}$\cr {{\rm C}}_{2}{{\rm H}}_{5}{\rm O}{\rm H}+3{{\rm H}}_{2}{\rm O}\to 2{\rm C}{{\rm O}}_{2}+12{{\rm H}}^{+}+12{{\rm e}}^{-}\hfill\cr}}$$$ …”