Evolution mechanisms and kinetics of porous structures during chemical dealloying of binary alloys

Jie Li, Shenyang Hu, Yulan Li, San Qiang Shi

Research output: Journal article publicationJournal articleAcademic researchpeer-review

Abstract

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.

Original languageEnglish
Article number111092
JournalMicroporous and Mesoporous Materials
Volume320
DOIs
Publication statusPublished - Jun 2021

Keywords

  • Chemical dealloying
  • Multi-phase-field model
  • Nanoporous

ASJC Scopus subject areas

  • Chemistry(all)
  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials

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