The Promoting Effect of Europium on PtSn/C Catalyst for Ethanol Oxidation

Abstract

Well‐dispersed PtSnEu/C and PtSn/C catalysts were prepared by the impregnation–reduction method using formic acid as a reductant and characterised by X‐ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersion X‐ray spectroscopy (EDX) and X‐ray photoelectron spectroscopy (XPS). The synthesised catalysts with different atomic ratios of Pt/Sn/Eu have the Pt face centered cubic (fcc) structure and their particle sizes are 3–4 nm. The PtSnEu/C catalyst is composed of many Pt (0), SnO2, Eu(OH)3, a small amount of Pt(II) and partly alloyed PtSn, but no metallic Eu. The electrochemical measurements indicate that in comparison with Pt3Sn1/C catalyst, the Pt3Sn1Eu1/C catalyst for ethanol oxidation has more negative onset potential, smaller apparent activation energy and lower electrochemical impedance so that it exhibits very high catalytic activity. Its peak current density increases by 135% and 40%, compared with Pt3Sn1/C and Pt1Ru1/C (JM) catalysts, respectively. This is because the Eu(OH)3 formed by adding Eu to PtSn/C catalyst can provide the OH group which is in favour of the removal of adsorbed intermediates and ethanol oxidation.

Pt‐Sn‐Eu/C Catalysts: Application of Rare Earth Metals as Anodes in Direct Ethanol Fuel Cells

“…The Pt-Sn/C catalyst exhibits the greatest degree of Pt-Sn alloying. The lattice parameter obtained by this method ranged from 0.3927 to 0.3929 nm and the alloying degree was 17% for a Pt-Sn-Eu/C composition close to 65:25:10 [17]. The 50:30:20 Pt-Sn-Eu/C catalyst exhibited a 27% alloying degree, close to that of the commercial Pt-Sn/C catalyst.…”

“…Jacob et al [15] studied a Pt-Sn-Ce/C catalyst synthesized using a formic-acid method, and there was some beneficial effect from adding Ce to Pt-Sn. Wang et al [17] prepared carbon supported Pt-Sn-Eu and Pt-Sn nanocatalysts and their results showed that adding Eu to the Pt-Sn/C catalyst significantly enhanced its activity toward ethanol oxidation in an acidic medium. Wang et al [17] prepared carbon supported Pt-Sn-Eu and Pt-Sn nanocatalysts and their results showed that adding Eu to the Pt-Sn/C catalyst significantly enhanced its activity toward ethanol oxidation in an acidic medium.…”

“…Corradini et al [16] synthesized a Pt-Sn-Pr/C catalyst using the same method, with the Pr increasing the EOR electroactivity of Pt and Pt-Sn. However, the authors of these studies noted that the EOR activity of the various catalysts studied might be improved by altering their physical proprieties, for example by preparing smaller particle sizes and Pt-Sn alloys [15][16][17]. However, the authors of these studies noted that the EOR activity of the various catalysts studied might be improved by altering their physical proprieties, for example by preparing smaller particle sizes and Pt-Sn alloys [15][16][17].…”

“…Corradini et al [16] synthesized a Pt-Sn-Pr/C catalyst using the same method, with the Pr increasing the EOR electroactivity of Pt and Pt-Sn. Wang et al [17] prepared carbon supported Pt-Sn-Eu and Pt-Sn nanocatalysts and their results showed that adding Eu to the Pt-Sn/C catalyst significantly enhanced its activity toward ethanol oxidation in an acidic medium. However, the authors of these studies noted that the EOR activity of the various catalysts studied might be improved by altering their physical proprieties, for example by preparing smaller particle sizes and Pt-Sn alloys [15][16][17].…”

Investigation of Nanometals (Ni and Sn) in Platinum-Based Ternary Electrocatalysts for Ethanol Electro-oxidation in Membraneless Fuel Cells

“…Considerable efforts have been directed toward the development of effective electrocatalysts that can oxidize ethanol at lower potentials [8][9][10]. For example, alloys of Pt with other elements such as Ru, Rh, Ir, Mo, W, Sn, and Ni have been frequently studied as co-catalysts to minimize the effect of Pt poisoning with CO and other byproducts, thereby improving the catalytic activity [11][12][13][14][15][16].…”