Design of PdAg Hollow Nanoflowers through Galvanic Replacement and Their Application for Ethanol Electrooxidation

Abstract

In this study, galvanic replacement provides a simple route for the synthesis of PdAg hollow nanoflower structures by using the Ag-seeds as sacrificial templates in the presence of l-ascorbic acid (reductant) and CTAC (capping agent). Transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and EDS mapping were used to characterize the as-prepared PdAg hollow nanoflower catalysts, where they were alloyed nanoflower structures with hollow interiors. By maneuvering the Pd/Ag ratio, we found that the as-prepared Pd Ag hollow nanoflower catalysts had the optimized performance for catalytic activity toward ethanol oxidation reaction. Moreover, these as-prepared PdAg hollow nanoflower catalysts exhibited noticeably higher electrocatalytic activity as compared to pure Pd and commercial Pd/C catalysts due to the alloyed Ag-Pd composition as well as the hollow nanoflower structures. It is anticipated that this work provides a rational design of other architecturally controlled bimetallic nanocrystals for application in fuel cells.

Pt Islands on 3 D Nut‐like PtAg Nanocrystals for Efficient Formic Acid Oxidation Electrocatalysis

“…[26] For the synthesis of smooth PtAg "nuts", the appropriate amount of H 2 PtCl 6 and CTAC (30 mg) were added to ag lass vial containing deionized water (5 mL) with rapid stirring. [26] For the synthesis of smooth PtAg "nuts", the appropriate amount of H 2 PtCl 6 and CTAC (30 mg) were added to ag lass vial containing deionized water (5 mL) with rapid stirring.…”

“…The typical Ag seeds were prepared according to am ethod similar to some reported researches. [26] For the synthesis of smooth PtAg "nuts", the appropriate amount of H 2 PtCl 6 and CTAC (30 mg) were added to ag lass vial containing deionized water (5 mL) with rapid stirring. After that, freshly-prepared Ag seeds (5 mL) were dropped onto the above aqueous solution.…”

Nanocatalysts for Electrocatalytic Oxidation of Ethanol

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Newly Designed Ternary Metallic PtPdBi Hollow Catalyst with High Performance for Methanol and Ethanol Oxidation

“…Catalysts with well-controlled morphology are promising materials with improved physical and chemical properties [20]. Plenty of examples can be found in literature with respect to the fascinated structures, including nanoflowers [21], nanowires [22], nanotubes [23], nanosheets [24], nanocubes [25] and hollow-structured nanoparticles [26]. Typically, the hollow structure has been investigated in recent years because of its stability, consecutive reactions and improved selectivity of catalytic reactions [14,27].…”