Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), School of Materials Science and Engineering, Shandong University, Jingshi Road 17923, Jinan 250061, P.R. China
Ying Zhang
Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), School of Materials Science and Engineering, Shandong University, Jingshi Road 17923, Jinan 250061, P.R. China
Bin Yu
Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), School of Materials Science and Engineering, Shandong University, Jingshi Road 17923, Jinan 250061, P.R. China
Kuibo Yin
SEU-FEI Nano-Pico Center, Key Lab of MEMS of Ministry of Education, Southeast University, Nanjing 210096, P.R. China
Jingyu Qin
Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), School of Materials Science and Engineering, Shandong University, Jingshi Road 17923, Jinan 250061, P.R. China
Zhonghua Zhang
Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education), School of Materials Science and Engineering, Shandong University, Jingshi Road 17923, Jinan 250061, P.R. China; Corresponding author
Summary: 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.
