TY - JOUR
T1 - Evolution mechanisms and kinetics of porous structures during chemical dealloying of binary alloys
AU - Li, Jie
AU - Hu, Shenyang
AU - Li, Yulan
AU - Shi, San Qiang
N1 - Funding Information:
This study was supported by a grant from the Research Grants Council of Hong Kong ( PolyU 152174/17E) .
Publisher Copyright:
© 2021 Elsevier Inc.
PY - 2021/6
Y1 - 2021/6
N2 - Chemical dealloying beckons researchers both for scientific interest in corrosion failure of metallic materials and for the fabrication of nanoporous materials that have versatile applications due to their ultra-high surface area. Empirically, nanoporous structure evolves by the corrosion of less noble elements coupled with the rearrangement of more noble elements in the alloys. However, how topologically complex porous structures form and how environmental and material factors affect the dealloying kinetics are still unknown. This work develops a multi-phase-field model to demonstrate that a nucleation-growth mechanism can explain the formation of nanoporous structures under chemical attack. The evolution of nanoporous patterns from a binary alloy is examined as a function of the chemical content of the electrolyte, precursor alloy composition, dimensionality, and bulk and surface diffusion coefficients, which is validated with experimental observations. Two-phase composite dealloying and the effect of defect pre-existed in the precursor are also presented. The comprehensive model developed in this study provides a powerful tool to tailor made nanoporous metallic structures under chemical dealloying.
AB - Chemical dealloying beckons researchers both for scientific interest in corrosion failure of metallic materials and for the fabrication of nanoporous materials that have versatile applications due to their ultra-high surface area. Empirically, nanoporous structure evolves by the corrosion of less noble elements coupled with the rearrangement of more noble elements in the alloys. However, how topologically complex porous structures form and how environmental and material factors affect the dealloying kinetics are still unknown. This work develops a multi-phase-field model to demonstrate that a nucleation-growth mechanism can explain the formation of nanoporous structures under chemical attack. The evolution of nanoporous patterns from a binary alloy is examined as a function of the chemical content of the electrolyte, precursor alloy composition, dimensionality, and bulk and surface diffusion coefficients, which is validated with experimental observations. Two-phase composite dealloying and the effect of defect pre-existed in the precursor are also presented. The comprehensive model developed in this study provides a powerful tool to tailor made nanoporous metallic structures under chemical dealloying.
KW - Chemical dealloying
KW - Multi-phase-field model
KW - Nanoporous
UR - http://www.scopus.com/inward/record.url?scp=85104110640&partnerID=8YFLogxK
U2 - 10.1016/j.micromeso.2021.111092
DO - 10.1016/j.micromeso.2021.111092
M3 - Journal article
AN - SCOPUS:85104110640
VL - 320
JO - Zeolites
JF - Zeolites
SN - 1387-1811
M1 - 111092
ER -