Temperature Induced Dimensional Tuning and Anomalous Deformation of Micro/Nanopores

Artificial nanopores have become a common toolbox in nanotechnologies, with dimension and geometry as predominant factors. Most fabrication technologies determine the pore size beforehand, but few exist that enable size-tuning post-manufacturing. In this work, we reported a type of ion track etched micro/nanopores on uniaxially drawn PET foils that enable irreversible thermal shrinkage, thus tuning the pore dimensions by increasing ambient temperatures. Importantly, we found a complex pore deformation process, which for a specific range of pore sizes and temperatures resulted in a peculiar eye-shaped appearance of the pore openings. We analyzed the mechanical stresses and theoretically illustrated the complex deformation process by a phase diagram. Temperature-induced dimensional tuning nanopores reduced maximally over 98% of ionic conduction in a single nanopore and 99% of pressure-driven flow in a pore-array membrane within few seconds at 90 degrees C, which is useful for temperature-modulated mass transport in nanotechnology and energy applications.

Automated summary

Artificial nanopores with tunable dimensions were created on PET foils, enabling size adjustment through irreversible thermal shrinkage by increasing ambient temperatures. The complex pore deformation process and mechanical stresses were analyzed and theoretically illustrated using a phase diagram. These temperature-induced nanopores significantly reduced ionic conduction and pressure-driven flow, making them useful for temperature-modulated mass transport in nanotechnology and energy applications.