Shape regulation of high-index facet nanoparticles by dealloying

Tetrahexahedral particles (~10 to ~500 nanometers) composed of platinum (Pt), palladium, rhodium, nickel, and cobalt, as well as a library of bimetallic compositions, were synthesized on silicon wafers and on catalytic supports by a ligand-free, solid-state reaction that used trace elements [antimony (Sb), bismuth (Bi), lead, or tellurium] to stabilize high-index facets. Both simulation and experiment confirmed that this method stabilized the {210} planes. A study of the PtSb system showed that the tetrahexahedron shape resulted from the evaporative removal of Sb from the initial alloy—a shape-regulating process fundamentally different from solution-phase, ligand-dependent processes. The current density at a fixed potential for the electro-oxidation of formic acid with a commercial Pt/carbon catalyst increased by a factor of 20 after transformation with Bi into tetrahexahedral particles.

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The in situ etching assisted synthesis of Pt–Fe–Mn ternary alloys with high-index facets as efficient catalysts for electro-oxidation reactions

Nanoscale ◽

10.1039/c8nr10231g ◽

2019 ◽

Vol 11 (18) ◽

pp. 9061-9075 ◽

Cited By ~ 21

Author(s):

Congli Qin ◽

Aixin Fan ◽

Xin Zhang ◽

Xiaoping Dai ◽

Hui Sun ◽

...

Keyword(s):

High Index ◽

Ternary Alloys ◽

Oxidation Reactions ◽

Electro Oxidation ◽

Novel Strategy

A novel strategy for significantly enhancing electro-oxidation reactions based on the reconstruction of Pt-based alloys with HIFs is demonstrated.

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High-index faceted Pt-Ru alloy concave nanocubes with enhancing ethanol and CO electro-oxidation

Electrochimica Acta ◽

10.1016/j.electacta.2021.139266 ◽

2021 ◽

pp. 139266

Author(s):

Lu Wei ◽

Feng Liu ◽

Xin Jiang ◽

Yu-Han Yang ◽

Tian Sheng ◽

...

Keyword(s):

High Index ◽

Electro Oxidation

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Guided Mode Resonance in a Low-Index Waveguide Layer

Applied Sciences ◽

10.3390/app11083312 ◽

2021 ◽

Vol 11 (8) ◽

pp. 3312

Author(s):

Tingbiao Guo ◽

Julian Evans ◽

Nan Wang ◽

Yi Jin ◽

Jinlong He ◽

...

Keyword(s):

Total Internal Reflection ◽

Field Enhancement ◽

Functional Materials ◽

High Index ◽

Waveguide Layer ◽

Geometrical Parameters ◽

Guided Mode ◽

Metal Grating ◽

Simulation And Experiment ◽

Guided Mode Resonance

In this paper, we show that the guided mode resonance can exist in a low-index waveguide layer on top of a high-index substrate. With the help of the interaction of diffraction from a metal grating and total internal reflection effects, we verify that the guided mode can be supported in the low-index SU8 layer on a high-index substrate. Simulation and experiment show the resonant wavelength can be simply manipulated by controlling the geometrical parameters of the metal grating and waveguide layer. This structure extends the possibilities of guided-mode resonance to a broader class of functional materials and may boost its use in applications such as field enhancement, sensing and display.

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Fabrication of a mesoporous Pt-carbon catalyst by the direct templating of mesoporous Pt-alumina for the methanol electro-oxidation

Journal of Power Sources ◽

10.1016/j.jpowsour.2005.07.032 ◽

2006 ◽

Vol 157 (1) ◽

pp. 196-200 ◽

Cited By ~ 17

Author(s):

Heesoo Kim ◽

Pil Kim ◽

Ji Bong Joo ◽

Wooyoung Kim ◽

In Kyu Song ◽

...

Keyword(s):

Carbon Catalyst ◽

Electro Oxidation

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Pt3Mn alloy nanostructure with high-index facets by Sn doping modified for highly catalytic active electro-oxidation reactions

Journal of Catalysis ◽

10.1016/j.jcat.2020.12.034 ◽

2021 ◽

Author(s):

Yunrui Li ◽

Yao Wang ◽

Shuna Li ◽

Mingxuan Li ◽

Yujie Liu ◽

...

Keyword(s):

High Index ◽

Oxidation Reactions ◽

Sn Doping ◽

Electro Oxidation

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Formation of Pt-Based Alloy Nanoparticles Assisted by Molybdenum Hexacarbonyl

Nanomaterials ◽

10.3390/nano11071825 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1825

Author(s):

Gerard M. Leteba ◽

David R. G. Mitchell ◽

Pieter B. J. Levecque ◽

Eric van Steen ◽

Candace I. Lang

Keyword(s):

High Performance ◽

Morphological Evolution ◽

High Index ◽

Solution Phase ◽

Alloy Nanoparticles ◽

Molybdenum Hexacarbonyl ◽

Metal Precursors ◽

Synthetic Procedure ◽

Selection Of

We report on an optimized, scalable solution-phase synthetic procedure for the fabrication of fine-tuned monodisperse nanostructures (Pt(NiCo), PtNi and PtCo). The influence of different solute metal precursors and surfactants on the morphological evolution of homogeneous alloy nanoparticles (NPs) has been investigated. Molybdenum hexacarbonyl (Mo(CO)6) was used as the reductant. We demonstrate that this solution-based strategy results in uniform-sized NPs, the morphology of which can be manipulated by appropriate selection of surfactants and solute metal precursors. Co-surfactants (oleylamine, OAm, and hexadecylamine, HDA) enabled the development of a variety of high-index faceted NP morphologies with varying degrees of curvatures while pure OAm selectively produced octahedral NP morphologies. This Mo(CO)6-based synthetic protocol offers new avenues for the fabrication of multi-structured alloy NPs as high-performance electrocatalysts.

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