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Inverse iron oxide/metal catalysts from galvanic replacement.

ABSTRACT: Key chemical transformations require metal and redox sites in proximity at interfaces; however, in traditional oxide-supported materials, this requirement is met only at the perimeters of metal nanoparticles. We report that galvanic replacement can produce inverse FeO_x/metal nanostructures in which the concentration of oxide species adjoining metal domains is maximal. The synthesis involves reductive deposition of rhodium or platinum and oxidation of Fe²⁺ from magnetite (Fe₃O₄). We discovered a parallel dissolution and adsorption of Fe²⁺ onto the metal, yielding inverse FeO_x-coated metal nanoparticles. This nanostructure exhibits the intrinsic activity in selective CO₂ reduction that simple metal nanoparticles have only at interfaces with the support. By enabling a simple way to control the surface functionality of metal particles, our approach is not only scalable but also enables a versatile palette for catalyst design.

SUBMITTER: Zhu Y

PROVIDER: S-EPMC7324589 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature

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Inverse iron oxide/metal catalysts from galvanic replacement.

Zhu Yifeng Y Zhang Xin X Koh Katherine K Kovarik Libor L Fulton John L JL Rosso Kevin M KM Gutiérrez Oliver Y OY

Nature communications 20200629 1

Key chemical transformations require metal and redox sites in proximity at interfaces; however, in traditional oxide-supported materials, this requirement is met only at the perimeters of metal nanoparticles. We report that galvanic replacement can produce inverse FeO<sub>x</sub>/metal nanostructures in which the concentration of oxide species adjoining metal domains is maximal. The synthesis involves reductive deposition of rhodium or platinum and oxidation of Fe<sup>2+</sup> from magnetite (Fe ...[more]

PMID: 32601487

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