Lithium encapsulation in etched nuclear pores in polyethylene terephthalate

Abstract

Encapsulation of lithium in ion-track etched polymer has been studied using both ion and neutron-based techniques. Latent tracks have been formed in Polyethylene terephthalate foils by irradiation with high energy Xe26 + ions. Subsequently, the latent-tracks have been developed, via chemical etching. The resulting pore shapes have been characterized by Ion Transmission Spectroscopy. From the analysis of the energy spectra of the ions transmitted through the membrane, it was possible to estimate pores' inner geometry and its evolution during etching. The etched foils were exposed to a LiCl aqueous solution and the depth distribution of Li incorporated into the pores was examined by implementing the Neutron Depth Profiling technique. The ability of the membrane to encapsulate the lithium in pores, was determined. The present study can be relevant to several applications, e.g., lithium-ion batteries and biosensors, where an in-depth knowledge of the pores' shape/size and of their trapping capability is required.