Understanding the thermal stability of hollow metal nanoframes remains a significant challenge due to strongly coupled effects such as porosity, curvature, and defect migration. Using tight-binding Monte Carlo simulations, we systematically investigate gold and silver nanoframes with cavity radii of 7.0–19.9 Å and quantitatively resolve their structural evolution through a shape-parametrization method that tracks cavity collapse and global flattening with ångström-level precision. Silver nanoframes exhibit lateral pore closure at 605–785 K, cavity collapse at 783–844 K, and melting near 852–900 K. Gold analogues show earlier pore closure (585–720 K) but higher collapse temperatures (688–823 K) and melting at 772–825 K, consistent with more coordinated recrystallization. The flattening parameter rises to 0.18–0.22 before global deformation, serving as a universal geometric indicator. Together, these quantitative criteria advance mechanistic understanding and enable the predictive design of thermally robust porous metal nanostructures.
Myasnichenko et al. (Sun,) studied this question.