Pd₂Sn [010] nanorods as a highly active and stable ethanol oxidation catalyst

Abstract

The development of highly active, low cost and stable electrocatalysts for direct alcohol fuel cells remains a critical challenge. While Pd2Sn has been reported as an excellent catalyst for the ethanol oxidation reaction (EOR), here we present DFT analysis results showing the (100) and (001) facets of orthorhombic Pd2Sn to be more favourable for the EOR than (010). Accordingly, using tri-n-octylphosphine, oleylamine (OLA) and methylamine hydrochloride as size and shape directing agents, we produced colloidal Pd2Sn nanorods (NRs) grown in the [010] direction. Such Pd2Sn NRs, supported on graphitic carbon, showed excellent performance and stability as an anode electrocatalyst for the EOR in alkaline media, exhibiting 3 times and 10 times higher EOR current densities than that of Pd2Sn and Pd nanospheres, respectively. We associate this improved performance with the favourable faceting of the NRs.Peer ReviewedPostprint (published version

Intermetallic Nanocrystals: Syntheses and Catalytic Applications

“…The use of TOP played an important role in facilitating the formation of the cubic shape by capping their {100} facets via selective adsorption of P‐based groups derived from TOP (Figure d). Recently, Cabot and co‐workers demonstrated the synthesis of orthogonal Pd 2 Sn nanorods (space group: Pnma) with different aspect ratios in OAm containing hexadecylammonium chloride (HDA·HCl) or methylamine hydrochloride (MAHC) with TOP as a stabilizer and capping agent at 300 °C ( Figure ) . The authors found that Cl – ions derived from HDA·HCl or MAHC could selectively desorb TOP from the {010} facets on the two ends of a nanorod, leading to anisotropic growth (Figure a).…”

“…b–e) TEM images of the Pd 2 Sn nanoparticles and nanorods with different lengths and diameters achieved by varying the concentration of Cl – ions and TOP. b–e) Reproduced with permission . Copyright 2016, The Royal Society of Chemistry.…”

Palladium Nanoparticles Supported on B‐Doped Carbon Nanocage as Electrocatalyst toward Ethanol Oxidation Reaction

“…It reveals that the 336.7 eV binding energy of Pd/BC-2 matched with representational Pd 3d signal peak. [56] The Pd (0) has more comparative valence than Pd (II) state in the Pd/BC-2 on account of the cumulative strength ratio. [55] The binding energy of Pd (0) appears at 336.1 eV (Pd 3d 5/ 2 ) and 341.45 eV (Pd 3d 3/2 ), while these of Pd (II) state can be seen at 336.9 eV (3d 5/2 ) and 342.4 eV (3d 3/2 ).…”

“…[55] The binding energy of Pd (0) appears at 336.1 eV (Pd 3d 5/ 2 ) and 341.45 eV (Pd 3d 3/2 ), while these of Pd (II) state can be seen at 336.9 eV (3d 5/2 ) and 342.4 eV (3d 3/2 ). [56] The Pd (0) has more comparative valence than Pd (II) state in the Pd/BC-2 on account of the cumulative strength ratio. Compared to binding energy (188.0 eV) of the pure boron, the higher shift of the B 1s signal reveals that the sp 2 carbon lattice exists boron.…”

Nanocatalysts for Electrocatalytic Oxidation of Ethanol

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