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Porous gold with three-level structural hierarchy.

ABSTRACT: Facilitating the mass transfer and enlarging the active surface area are two mutually exclusive demands in porous materials, while structural hierarchy could settle this issue by constructing continuous channels with different length scales. However, it is a great challenge to fabricate porous metallic materials with three or more geometrically similar hierarchy levels. Herein, a novel strategy combining vapor phase dealloying with electrochemical dealloying is proposed to achieve nanoporous gold (NPG) with three-level nested hierarchy (N³PG), in which the length scale covers micron (5866.8 ± 1445.5 nm), submicron (509.9 ± 106.0 nm), and nanometer (20.1 ± 3.0 nm) for each level. Notably, the structural superiority of such material is manifested by its faster charge transfer behaviors, as benchmarked with unimodal and bimodal NPG (N¹PG and N²PG). The present strategy is of great potential to fabricate other hierarchically porous metals with enhanced functional and structural properties.

SUBMITTER: Shi Y

PROVIDER: S-EPMC9515608 | biostudies-literature | 2022 Oct

REPOSITORIES: biostudies-literature

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Porous gold with three-level structural hierarchy.

Shi Yujun Y Zhang Ying Y Yu Bin B Yin Kuibo K Qin Jingyu J Zhang Zhonghua Z

iScience 20220911 10

Facilitating the mass transfer and enlarging the active surface area are two mutually exclusive demands in porous materials, while structural hierarchy could settle this issue by constructing continuous channels with different length scales. However, it is a great challenge to fabricate porous metallic materials with three or more geometrically similar hierarchy levels. Herein, a novel strategy combining vapor phase dealloying with electrochemical dealloying is proposed to achieve nanoporous gol ...[more]

PMID: 36185372

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