One-pot synthesis of Au@Pd/graphene nanostructures: electrocatalytic ethanol oxidation for direct alcohol fuel cells (DAFCs)

Abstract

Surfactant-free bimetallic Au@Pd core-shell NPs on graphene sheets were fabricated from Au, Pd ions and graphene oxide by one-step reduction using ascorbic acid as an eco-friendly reducing agent. Au@Pd NPs with about 7 nm size are evenly distributed on the surface of graphene. The core/shell structures were confirmed with X-ray diffraction (XRD) and High-angle annual dark field scanning transmission microscopy (HAADF-STEM) mapping analysis. Prepared Au@Pd/graphene nanocomposites show an excellent electrocatalytic activity toward ethanol oxidation: I f value that was the best for our catalysts is 11.6 A mg 21 , which is about 5 times as high as that of the previous catalyst. The data resulted from extremely optimized bimetallic structure of a small Au core and a thin Pd shell. Pd atoms are constantly encouraged by adjacent Au atoms.

Microbial synthesis of Pd/Fe3O4, Au/Fe3O4 and PdAu/Fe3O4 nanocomposites for catalytic reduction of nitroaromatic compounds

“…SHE) is higher than that of Pd(II) ( E 0 PdCl4 2− /Pd = +0.6 V vs . SHE) 35 . Therefore, Au(III) is preferentially reduced by microbial components and extracellular polymeric substance ( E 0 = −0.32 to −0.1 V vs .…”

Synthesis of open-mouthed, yolk–shell Au@AgPd nanoparticles with access to interior surfaces for enhanced electrocatalysis

“…3,4 Thus, Pd/Au composite nanoparticles (NPs) with bimetallic alloy and core-shell (CS) structures have been successfully developed to catalyze various electrochemical reactions. [5][6][7][8][9][10] However, they lead almost no real improvement in Pd catalysis performance as compared with Pd nanoparticles because these structures still rely on the exterior surfaces of Pd shells to perform the electrocatalysis, very similar to conventional Pd nanoparticles. Moreover, it is still expensive to utilize especially when the use of Au does not add any value in catalysis.…”

Synchronized synthesis of Pd@C-RGO carbocatalyst for improved anode and cathode performance for direct ethylene glycol fuel cell

“…12,13 Recently, RGO and/or metal NPs have been synthesized using various green reducing agents such as sugar, wild carrot, ascorbic acid (AA) and amino acids etc. [14][15][16][17][18][19] Of these, AA shows excellent reduction activity on both the metal and graphene oxide. Earlier studies on the reduction reaction performed in an aqueous medium 14,15 revealed that AA has a strong affinity with the aqueous medium, resulting in the formation of metallic clusters, albeit with reduced catalytic activity.…”