A Kinetic Model for Etching Nanoarchitectonics of Networked Solids via Pore Nucleation and Growth: Insights from Network Science and Experimental Validation

The dissociation of networked solids in corrosive liquids is of critical importance for processes such as cavity/pore fabrication, shaping, compositing, recycling, as well as guest storage and manipulation. However, the related quantitative kinetics remain unclear, hindering precise and autonomous processing-structure−property design. In this work, we develop a theory to describe the etching kinetics of networked solids that undergo etching through a pore-formation pathway. By analogizing to nucleation and growth of new phases during phase transformations, we proposed a nucleation-growth model for pores and established quantitative relationships among etching fraction, pore growth rate, and etching kinetics. The theoretical etching kinetics was validated by the experimental data from etching experiments on Prussian blue crystals and by network science simulation on simple-cubic lattices. Using network science simulations, we further revealed that the kinetics exponent k decreases as the vacancy fraction increases, which predicts 1D growth of pores at high vacancy fractions. This prediction was demonstrated by etching experiments on Prussian blue mesocrystals, suggesting the potential of the derived model in guiding the etching nanoarchitectonics of networked solids.