The role of Pt-FexOy interfacial sites for CO oxidation

Ro, Insoo; Aragão, Isaias Barbosa; Chada, Joseph P.; Liu, Yifei; Rivera-Dones, Keishla R.; Ball, Madelyn R.; Zanchet, Daniela; Dumesic, James A.; Huber, George W.

doi:10.1016/j.jcat.2017.11.021

Cited by 49 publications

(24 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Catalyst Synthesis: A series of CeO x -Pd/C catalysts were synthesized by selective deposition of CeO x onto carbon-supported Pd nanoparticles by controlled surface reactions (CSR). [57][58][59][60][61][70][71][72][73][74][75][76][77] First, a 10 wt% Pd/C catalyst was prepared by wet impregnation by adding a solution of 0.84 g of palladium (II) acetate in 100 mL of dichloromethane to 3.6 g of Vulcan XC-72 carbon. The mixture was stirred in an open vessel at 323 K to evaporate the solvent.…”

Section: Methodsmentioning

confidence: 99%

Synthesis of CeO_x‐Decorated Pd/C Catalysts by Controlled Surface Reactions for Hydrogen Oxidation in Anion Exchange Membrane Fuel Cells

Singh

Davydova

Douglin

et al. 2020

Adv Funct Materials

View full text Add to dashboard Cite

Due to the sluggish kinetics of the hydrogen oxidation reaction (HOR) in alkaline electrolytes, the development of more efficient HOR catalysts is essential for the next generation of anion‐exchange membrane fuel cells (AEMFCs). In this work, CeOx is selectively deposited onto carbon‐supported Pd nanoparticles by controlled surface reactions, aiming to enhance the homogenous distribution of CeOx and its preferential attachment to Pd nanoparticles, to achieve highly active CeOx‐Pd/C catalysts. The catalysts are characterized by inductively coupled plasma–atomic emission spectroscopy, X‐ray diffraction, high‐resolution transmission electron microscopy, scanning transmission electron microscopy (STEM), electron energy loss spectroscopy, and X‐ray photoelectron spectroscopy to confirm the bulk composition, phases present, morphology, elemental mapping, local oxidation, and surface chemical states, respectively. The intimate contact between Pd and CeOx is shown through high‐resolution STEM maps. The oxophilic nature of CeOx and its effect on Pd are probed by CO stripping. The interfacial contact area between CeOx and Pd nanoparticles is calculated for the first time and correlated to the electrochemical performance of the CeOx‐Pd/C catalysts. Highest recorded HOR specific exchange current (51.5 mA mg−1Pd) and H2–O2 AEMFC performance (peak power density of 1,169 mW cm−2 mgPd−1) are obtained with a CeOx‐Pd/C catalyst with Ce0.38/Pd bulk atomic ratio.

show abstract

Section: Methodsmentioning

confidence: 99%

Synthesis of CeO_x‐Decorated Pd/C Catalysts by Controlled Surface Reactions for Hydrogen Oxidation in Anion Exchange Membrane Fuel Cells

Singh

Davydova

Douglin

et al. 2020

Adv Funct Materials

View full text Add to dashboard Cite

show abstract

“…For example, Pu et al successfully grew a flexible MoP nanosheet array on a carbon cloth and a film of semimetallic MoP 2 nanoparticles on a metal Mo plate as active, stable, and binder-free electrodes for HER over a wide pH range. Other literature studies on the deposition of active catalysts on metal oxide substrates, such as TiO 2 , Fe x O y , MnO 2 , Co 3 O 4 , SnO 2 , CeO 2 , and Al 2 O 3 , ..., − have also been widely investigated for heterogeneous catalysis. Among these oxides, mesoporous Mn oxide substrates deposited with active catalysts were interestingly considered , because of the interesting properties of Mn oxides in oxidation reactions, likely related to the variable valency of Mn .…”

Section: Introductionmentioning

confidence: 99%

Constructing MoP_x@MnP_y Heteronanoparticle-Supported Mesoporous N,P-Codoped Graphene for Boosting Oxygen Reduction and Oxygen Evolution Reaction

et al. 2019

View full text Add to dashboard Cite

Developing efficient and cost-effective bifunctional electrocatalysts for both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is highly important for fabricating energy conversion and storage technologies, such as fuel cells, water electrolyzers, and metal–air batteries. Herein, we report a facile and economical route for synthesizing ultrasmall molybdenum phosphide (MoP y ) nanocrystal-attached mesoporous manganese phosphides on N,P-codoped graphene nanosheets, which display equivalent ORR (OER) activity to that of Pt/C (RuO2) catalysts. This is manifested by the positive onset potential (0.969 V) and half-wave potential (0.842 V) for ORR, as well as a mere overpotential of 301 mV at a current density of 20 mA·cm–2 and a small Tafel slope of 105 mV·dec–1 for OER in alkaline medium. It also demonstrates remarkable stability in comparison with Pt/C and RuO2 for both ORR and OER, respectively. The excellent performance can be attributed to the mesoporous structure with enhanced multiple types of electroactive sites, which highly favors the adsorption and catalyzation of reactants, as well as efficient reagent/product mass transport. The findings can pave a new way for the synthesis and usage of a hybrid as a bifunctional catalyst with high efficiency and outstanding longevity to enable next generation of energy conversion and storage.

show abstract

“…CO catalytic oxidation has attracted extensive attentions because of its significant applications in environmental governance and industrial catalysis 1–3. Although considerable efforts have been devoted to the surface and facets control of single‐phase catalysts (metal and metal oxide),4–6 it has been gradually revealed that heterogeneous architectures comprising metal nanoparticles on oxide surfaces result in better catalytic performance 7–9. The enhanced catalytic activity of heterogeneous architecture originates from the interaction of nanoparticle catalysts and the perimeter sites, along with charge transfer from the strong metal–metal oxidation 10,11.…”

Section: Introductionmentioning

confidence: 99%

Cu–Cu₂O Heterogeneous Architecture for the Enhanced CO Catalytic Oxidation

Kong

et al. 2020

Adv Materials Inter

View full text Add to dashboard Cite

surface of metal-metal oxidation can be oxidized. [12][13][14] Experimentally, relatively limited amount of group metals attached on catalyst surface present a tremendous potential in determining the active structure and composition during the CO oxidation. [15,16] Although noble metals (such as Au, Ag, and Ru) exhibit highly CO oxidation activities, [17][18][19] the rare quantity and high cost restrict their application. In contrast, transition metal oxides are of interest as the most suitable substitutes owing to the low cost and abundance. Among them, copper (Cu) and Cu-based materials are basically featured for CO oxidation, owning to the multiple oxidation states, such as cuprous oxide (Cu 2 O) and copper oxide (CuO). [20][21][22] Huang et al. have separately studied the CO oxidation activities over Cu, Cu 2 O, and CuO, and found that Cu 2 O exhibits higher activities than the other two copper species due to the propensity of Cu 2 O toward valence variations is easy to release or seize oxygen molecule. [23] Penkala et al. have prepared CuO-Ca 2 Fe 2 O 5 catalysts and studied the enhanced CO oxidation performance. [24] However, few appeared reports have concerned about the CO catalytic activity of Cu-Cu 2 O interface in oxygen atmospheres. From the previous theoretical perspective, the role of the loading particles focuses on the variations in work functions, the polarization at the interface of hybrid material, and the regulating and controlling of oxygen vacancy. [17,25] The lack of Cu-Cu 2 O heterogeneous interface and molecular understanding during the catalytic process remain unclear.Herein, we report a facile two-step synthesis approach for monodispersed Cu-Cu 2 O heterogeneous particles (HPs), where Cu nanoparticles on the surface were in situ reduced from octahedral Cu 2 O particles. Cu-Cu 2 O HPs were found to exhibit better catalytic performance than pure Cu 2 O particles during the first cycle of CO oxidation. In addition, after the first run of CO catalytic reaction, composite CuO-Cu 2 O interfaces are formed on the surface of Cu-Cu 2 O HPs, which further increased the conversion of CO oxidation efficiencies. The density functional theory (DFT) simulations indicate that due to loaded Cu nanoparticles, the heterogeneous architecture promotes the catalytic reaction under both the Eley-Rideal mechanism (key step: O 2 dissociation) as well as Langmuir-Hinshelwood mechanism. In Heterogeneous architecture of Cu 2 O-based composite has exhibited beneficial effort in the CO oxidation, due to the low cost and the multiple oxidation states. In this work, Cu-Cu 2 O heterogeneous particles (HPs) comprising uniformly distributed Cu nanoparticles anchored on the Cu 2 O surface are synthesized by in situ reduction reaction. Comparing with the pure Cu 2 O particles, Cu-Cu 2 O HPs exhibit enhanced and stable catalytic performance during CO oxidation. Moreover, both the transformation of interface and the role of loaded Cu nanoparticle at a molecular level are investigated to analyze the promotion, suggesting that ...

show abstract

The role of Pt-FexOy interfacial sites for CO oxidation

Cited by 49 publications

References 39 publications

Synthesis of CeO_x‐Decorated Pd/C Catalysts by Controlled Surface Reactions for Hydrogen Oxidation in Anion Exchange Membrane Fuel Cells

Synthesis of CeO_x‐Decorated Pd/C Catalysts by Controlled Surface Reactions for Hydrogen Oxidation in Anion Exchange Membrane Fuel Cells

Constructing MoP_x@MnP_y Heteronanoparticle-Supported Mesoporous N,P-Codoped Graphene for Boosting Oxygen Reduction and Oxygen Evolution Reaction

Cu–Cu₂O Heterogeneous Architecture for the Enhanced CO Catalytic Oxidation

Contact Info

Product

Resources

About

The role of Pt-FexOy interfacial sites for CO oxidation

Cited by 49 publications

References 39 publications

Synthesis of CeOx‐Decorated Pd/C Catalysts by Controlled Surface Reactions for Hydrogen Oxidation in Anion Exchange Membrane Fuel Cells

Synthesis of CeOx‐Decorated Pd/C Catalysts by Controlled Surface Reactions for Hydrogen Oxidation in Anion Exchange Membrane Fuel Cells

Constructing MoPx@MnPy Heteronanoparticle-Supported Mesoporous N,P-Codoped Graphene for Boosting Oxygen Reduction and Oxygen Evolution Reaction

Cu–Cu2O Heterogeneous Architecture for the Enhanced CO Catalytic Oxidation

Contact Info

Product

Resources

About

Synthesis of CeO_x‐Decorated Pd/C Catalysts by Controlled Surface Reactions for Hydrogen Oxidation in Anion Exchange Membrane Fuel Cells

Synthesis of CeO_x‐Decorated Pd/C Catalysts by Controlled Surface Reactions for Hydrogen Oxidation in Anion Exchange Membrane Fuel Cells

Constructing MoP_x@MnP_y Heteronanoparticle-Supported Mesoporous N,P-Codoped Graphene for Boosting Oxygen Reduction and Oxygen Evolution Reaction

Cu–Cu₂O Heterogeneous Architecture for the Enhanced CO Catalytic Oxidation