Star-shaped Pd@Pt core–shell catalysts supported on reduced graphene oxide with superior electrocatalytic performance

Kim, Young‐Min; Noh, Yuseong; Lim, Eun Ja; Lee, Seonhwa; Choi, Sung Mook

doi:10.1039/c4ta00070f

Cited by 170 publications

(96 citation statements)

References 78 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…[20][21][22][23] For instance, Youngmin Kim et al have prepared star-shaped core-shell PdPt nanoparticles on graphene sheets via a one-pot synthetic route, which presented a great improvement in the electrocatalytic performance towards the methanol oxidation reaction. 24 Yizhong Lu et al have reported a novel one-step synthetic strategy for the in situ synthesis of concave PtPd nanocubes on reduced GO nanosheets, which exhibited enhanced electrocatalytic activity and high durability toward methanol oxidation. 25 Herein, we report a facile synthesis of RGO-supported PdNi nanowire networks, using Ni as a template material with the assistance of a small amount of trisodium citrate at ambient temperature.…”

Section: Introductionmentioning

confidence: 99%

Facile synthesis of PdNi nanowire networks supported on reduced graphene oxide with enhanced catalytic performance for formic acid oxidation

et al. 2015

View full text Add to dashboard Cite

This paper reports a simple method, in which Ni nanoparticles act as seeds for the formation of reduced graphene oxide (RGO) supported PdNi nanowire networks. The as-prepared catalysts were characterized by transmission electron microscopy (TEM), high-resolution TEM (HRTEM), X-ray diffraction (XRD) and Xray photoelectron spectroscopy (XPS). Electrochemical measurements proved that the PdNi-NNs/RGO catalyst has superior electrocatalytic activity towards the formic acid oxidation reaction with much larger electrochemically active surface area and mass activity as well as higher long term-stability in comparison with the Pd/RGO and commercial Pd/C catalysts. The optimized ratio of Pd and Ni is 1 : 1, tuned by simply adjusting the feed ratio of the precursors as well. It is proposed that the improvement of the catalytic performance is attributed to the special nanostructure and the synergistic effect between Pd and Ni. These findings highlight the facile synthesis of the PdNi nanowire networks on RGO sheets and their promising application as electrocatalysts for fuel cells.

show abstract

Section: Introductionmentioning

confidence: 99%

Facile synthesis of PdNi nanowire networks supported on reduced graphene oxide with enhanced catalytic performance for formic acid oxidation

et al. 2015

View full text Add to dashboard Cite

show abstract

“…EXAFS is able to reveal short-range structural motifs responsible for catalyst activity enhancements, such as core-shell structures with surface reactivity modified by strain and ligand effects. [17][18][19] This has been shown in multiple examples of ORR catalysts for low-temperature fuel cell systems, where Pd has been used extensively as a promoter of Pt activity for the oxygen reduction reaction, [20][21][22][23][24][25] often in a Pd-core/Pt-shell morphology. Based on particle sizes derived from the XRD data, we stipulate that the catalyst particles are large enough to be nearly fully coordinated (N = 12 for fcc materials) .…”

Section: Resultsmentioning

confidence: 99%

Vapor-Deposited Pt and Pd-Pt Catalysts for Solid Acid Fuel Cells: Short Range Structure and Interactions with the CsH₂PO₄Electrolyte

Papandrew

John

Elgammal

et al. 2016

J. Electrochem. Soc.

View full text Add to dashboard Cite

State-of-the-art cathodes for solid acid fuel cells (SAFCs) based on the crystalline electrolyte CsH 2 PO 4 (CDP) are comprised of a proton-conducting CDP network coated by a vapor-deposited nanostructured catalyst. Pd-rich (85 at%Pd) Pt-Pd oxygen reduction catalysts vapor-deposited on CDP display both extraordinary activity for oxygen reduction and poor stability in cathodes for SAFCs operating at 250 • C. Similar catalysts with lower Pd content (57 at%Pd) are less active and more stable. Using X-ray absorption spectroscopy (XAS), we find that these catalysts are structurally similar and that structural variations are insufficient to explain the observed differences in activity. XAS and solid-state and solution nuclear magnetic resonance (NMR) also show that additional water-soluble chemical species are present in the Pd-rich electrode after fuel cell operation. We attribute the presence of these species to the reactivity of the Pd-rich catalyst with CsH 2 PO 4 and suggest that these products are the cause of the observed deactivation. Efficient, economical, reliable electricity generation from chemical fuels via electrochemical conversion has yet to be fully realized, despite considerable efforts to inject fuel cells into the technological mainstream. The slow adoption of these technologies can be traced in part to the high cost and low durability of electrolyte membranes, electrode materials, and other system components.1-4 Intermediatetemperature fuel cells 5 based on the crystalline proton conductor CsH 2 PO 4 (CDP) 6 are no exception to these constraints, despite desirable attributes that include fuel flexibility 7 and the prospect of platinum-free anodes. 8,9 In the case of air-breathing cells based on CDP, which we hereafter refer to as solid acid fuel cells (SAFCs), the major scientific challenges concern the activity and durability of the cathode. As an entirely solidstate technology, SAFC electrode performance is circumscribed by the extent of the tri-phase contact of electrolyte, catalyst, and oxidant in the electrode, a characteristic shared most closely with solid oxide fuel cells.10 State-of-the-art SAFC cathodes rely on the activation of all available cathode surface area by platinum coating, obtained via vapor deposition.11 In this electrode architecture, the Pt catalyst serves as both the oxygen reduction catalyst and the electronic conductor. Despite the utility of this configuration, the mass-normalized activity of Pt in SAFC cathodes remains unsatisfactory.12 Furthermore, the nature of the Pt-CDP interface is not well understood, and early studies have revealed the presence of unusual phenomena in this case. 13Understanding catalyst-CDP interactions is key to optimizing the performance of the SAFC cathode.A fleeting breakthrough for the SAFC cathode resulted from the deposition of Pt-Pd alloy catalysts on CDP.7,12 Pd-rich electrodes displayed activity enhancements of 450% compared with baseline Pt electrodes, for reasons that remain poorly understood. Furthermore, Pd-rich (>70 at% Pd) compos...

show abstract

“…Currently, graphene and its derivatives, as a kind of ideal carbonbased supports, have attracted considerable scientific interest. This is attributed to their excellent mechanical, electrical, and thermal properties, as well as their high specific surface area [23]. For example, Li and coworkers developed a one-pot strategy for the preparation of hierarchical dendritic garland-like PtPd nanostructures supported on reduced graphene oxide with significantly enhanced electrocatalytic activity and better stability toward methanol and ethanol oxidation in alkaline media [24].…”

Section: Introductionmentioning

confidence: 99%

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

Wisitruangsakul

Feng

et al. 2015

Electrochimica Acta

View full text Add to dashboard Cite

Star-shaped Pd@Pt core–shell catalysts supported on reduced graphene oxide with superior electrocatalytic performance

Abstract: A surfactantless, one-pot reduction approach for Pd@Pt core–shell nano-stars on reduced graphene oxide with enhanced catalytic activity and stability for methanol oxidation in alkaline media.

Cited by 170 publications

References 78 publications

Facile synthesis of PdNi nanowire networks supported on reduced graphene oxide with enhanced catalytic performance for formic acid oxidation

Facile synthesis of PdNi nanowire networks supported on reduced graphene oxide with enhanced catalytic performance for formic acid oxidation

Vapor-Deposited Pt and Pd-Pt Catalysts for Solid Acid Fuel Cells: Short Range Structure and Interactions with the CsH₂PO₄Electrolyte

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

Contact Info

Product

Resources

About

Star-shaped Pd@Pt core–shell catalysts supported on reduced graphene oxide with superior electrocatalytic performance

Abstract: A surfactantless, one-pot reduction approach for Pd@Pt core–shell nano-stars on reduced graphene oxide with enhanced catalytic activity and stability for methanol oxidation in alkaline media.

Cited by 170 publications

References 78 publications

Facile synthesis of PdNi nanowire networks supported on reduced graphene oxide with enhanced catalytic performance for formic acid oxidation

Facile synthesis of PdNi nanowire networks supported on reduced graphene oxide with enhanced catalytic performance for formic acid oxidation

Vapor-Deposited Pt and Pd-Pt Catalysts for Solid Acid Fuel Cells: Short Range Structure and Interactions with the CsH2PO4Electrolyte

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

Contact Info

Product

Resources

About

Vapor-Deposited Pt and Pd-Pt Catalysts for Solid Acid Fuel Cells: Short Range Structure and Interactions with the CsH₂PO₄Electrolyte