Structural Regulation of PdCu₂ Nanoparticles and Their Electrocatalytic Performance for Ethanol Oxidation

Abstract

Two types of PdCu nanoparticles were prepared through one-pot synthesis and a two-step reducing process, named as PdCu-1 and PdCu-2, respectively. The morphology and structure of as-prepared samples were investigated by transmission electron microscopy, high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and inductively coupled plasma-optical emission spectrometry. Results showed that more Pd atoms were buried in the inside of PdCu-1, whereas more available Pd sites were distributed on the surface of PdCu-2. The electrochemical measurements indicated that both PdCu-1 and PdCu-2 nanoparticles showed a higher electrocatalytic activity than that for pure Pd nanoparticles. In particular, PdCu-2 predictably exhibited a better stability and durability as well as a lower onset potential and a higher catalytic current density than that of PdCu-1 toward ethanol oxidation in alkaline media. On the basis of these studies, the formation mechanisms of both the PdCu catalysts and the relationship between their structure and properties were discussed in this paper.

Fabrication of tunable hierarchical MXene@AuNPs nanocomposites constructed by self-reduction reactions with enhanced catalytic performances

“…The rate of the pseudo-first-order reaction is 0.175 min −1 , indicating that the composite MXene@AuNPs20 had excellent catalytic activity for 4-NP. After eight consecutive catalytic cycles, the catalytic conversion was still more than 92%, indicating its superior stability in comparison with other kinds of composite catalysts [66][67][68][69][70][71], as shown in Fig. 7c.…”

Binary Pd−Ni Nanoalloy Particles over Carbon Support with Superior Alkaline Formate Fuel Electrooxidation Performance

“…[19] As presented in Figure 2a, in voltammograms recorded over the range of À 0.9-0.2 V vs Hg/HgO at room temperature, there is an obvious current increase for the PdÀ Ni catalyst, compared to that of Pd/C, with peaks atÀ 0.7 V, indicating the adsorption and desorption of hydrogen in the forward and backward scans, respectively. [19] As presented in Figure 2a, in voltammograms recorded over the range of À 0.9-0.2 V vs Hg/HgO at room temperature, there is an obvious current increase for the PdÀ Ni catalyst, compared to that of Pd/C, with peaks atÀ 0.7 V, indicating the adsorption and desorption of hydrogen in the forward and backward scans, respectively.…”

“…[12][13] As such, DFFCs currently need potential efficient and stable catalysts for widespread commer-cial applications. [17] When considering advancements in Pd-based anode catalysts for alkaline formate oxidation, transition metal alloying has been shown to increase the alcohol and formic acid/formate fuel oxidation capabilities [5,[18][19][20][21] and to the best of our knowledge, alkaline formate oxidation using Pd-transition metal alloy catalysts has seldom been studied and is largely unexplored. [14][15][16] However, there is an imminent need for performance improvements in Pd catalysts in terms of their efficiency and durability before they can be effectively utilized in alkaline DFFCs.…”

“…Palladium is the catalyst that has shown the most promising prospects for enhanced liquid-fuel oxidation kinetics in alkaline media and that could effectively replace platinum. [17] When considering advancements in Pd-based anode catalysts for alkaline formate oxidation, transition metal alloying has been shown to increase the alcohol and formic acid/formate fuel oxidation capabilities [5,[18][19][20][21] and to the best of our knowledge, alkaline formate oxidation using Pd-transition metal alloy catalysts has seldom been studied and is largely unexplored. Previous reports suggest that the formate oxidation reaction on the Pd surface proceeds through the decomposition of COO À into CO 3 2À in alkaline medium.…”

Nanocatalysts for Electrocatalytic Oxidation of Ethanol

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