Bond switching is responsible for nanoductility in zeolitic imidazolate framework glasses. Issue 18 (8th April 2021)

• Record Type: Journal Article
• Authors: To, Theany; Sørensen, Søren S.; Yue, Yuanzheng; Smedskjaer, Morten M.
• Is Part Of: Dalton transactions. Volume 50:Issue 18(2021)
• Page Start: 6126
• Page End: 6132
• Publication Date: 2021-04-08
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/d1dt00096a
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : The fracture mechanism of zeolitic imidazolate framework (ZIF) glasses is revealed to be associated with bond switching of organic linkers around central Zn nodes. The bond switching is more pronounced for ZIF glasses with smaller organic linkers. Abstract : Understanding of the fracture mechanism of metal–organic framework glasses remains limited. Using reactive molecular dynamics simulations, we here find that three zeolitic imidazolate framework glasses exhibit pronounced nanoductility upon fracture. This fracture behavior is confirmed by fracture toughness predictions. The results indicate that a model based on a purely brittle fracture significantly underestimates the simulated fracture toughness. We ascribe the nanoductility to a Zn–N bond switching mechanism, which is found to be more pronounced for smaller organic linkers. Thus, this study provides insights into the fracture mechanism of the low-toughness, yet nanoductile metal–organic framework glasses.