One-Pot Water-Based Synthesis of Pt–Pd Alloy Nanoflowers and Their Superior Electrocatalytic Activity for the Oxygen Reduction Reaction and Remarkable Methanol-Tolerant Ability in Acid Media

Abstract

Well-defined and strikingly monomorphic Pt–Pd alloy nanoflowers (Pt–Pd ANFs) with dominant {111} facets were successfully synthesized through a facile cochemical reduction method in a poly(allylamine hydrochloride) (PAH) based aqueous solution. The detailed morphology, composition, and structure of the Pt–Pd ANFs were investigated by transmission electron microscopy (TEM), selected-area electron diffraction (SAED), energy dispersive spectrum (EDS), nitrogen adsorption–desorption isotherms (SADI), EDS mapping, X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), demonstrating the Pt–Pd ANFs were highly porous and a self-supported structure. The formation mechanism of the Pt–Pd ANFs were investigated by TEM and Fourier transform infrared (FT-IR), indicating that the existence of PAH and rapid growth of crystal nuclei were essential for the formation of the Pt–Pd ANFs. The electrocatalytic activity and stability of the Pt–Pd ANFs for the oxygen reduction reaction (ORR) were investigated by rotating disk electrode voltammetry in 0.1 M HClO4 solution. The electrochemical tests indicated the {111}-enclosed Pt–Pd ANFs exhibited superior ORR activity along with satisfactory stability and methanol-tolerant ability under acidic conditions, which made them promising electrocatalysts for the future.

Spinel MnCo2O4 nanoparticles cross-linked with two-dimensional porous carbon nanosheets as a high-efficiency oxygen reduction electrocatalyst

“…S9 in the ESM). The onset potential for the ORR, which is defined as the potential corresponding to −10 μA·cm −2 , was used as an indicator of ORR activity [46]. It is worth noting that the MnCo 2 O 4 /C nanosheets show a very positive onset potential (0.945 V vs. RHE), close to that of the Pt/C catalyst (0.951 V vs. RHE) (Fig.…”

Biomolecule-assisted synthesis of porous PtPd alloyed nanoflowers supported on reduced graphene oxide with highly electrocatalytic performance for ethanol oxidation and oxygen reduction

“…After 200 cycles, the onset potential and current densities both remain unchanged (Fig. 8B), strongly manifesting the improved catalytic stability of porous PtPd NFs-RGO [55]. It is obviously related to the unique structure of PtPd NFs and RGO supporting function in this catalyst [53,56].…”

Simple wet-chemical synthesis of alloyed PdAu nanochain networks with improved electrocatalytic properties

“…4B 2 ), are well assigned to Pd 0 and Pd II species, respectively [6]. There is no evidence of PdO signals appeared between 335.4 and 337.5 eV (bulk Pd for 335.4 eV, PdO for 337.5 eV) [17].These observations reveal that Pd 0 is the predominant species with the percentage of 94.7%.…”

“…All the aqueous solutions were prepared with twice-distilled water throughout the whole experiments. 6 …”