Template Synthesis of Nanostructured Polymeric Membranes by Inkjet Printing.

The fabrication of functional nanomaterials with complex structures has been serving great scientific and practical interests, but current fabrication and patterning methods are generally costly and laborious. Here, we introduce a versatile, reliable, and rapid method for fabricating nanostructured polymeric materials. The novel method is based on a combination of inkjet printing and template synthesis, and its utility and advantages in the fabrication of polymeric nanomaterials is demonstrated through three examples: the generation of polymeric nanotubes, nanowires, and thin films. Layer-by-layer assembled nanotubes can be synthesized in a polycarbonate track-etched (PCTE) membrane by printing poly(allylamine hydrochloride) and poly(styrenesulfonate) sequentially. This sequential deposition of polyelectrolyte ink enables control over the surface charge within the nanotubes. By simply changing the printing conditions, polymeric nanotubes or nanowires were prepared by printing poly(vinyl alcohol) in a PCTE template. In this case, the high throughput nature of the method enables functional nanomaterials to be generated in under 3 minutes. Furthermore, we demonstrate that inkjet printing paired with template synthesis can be used to generate patterns comprised of chemically distinct nanomaterials. Thin polymeric films of layer-by-layer assembled poly(allylamine hydrochloride) and poly(styrenesulfonate) are printed on a PCTE membrane. Track-etched membranes covered with the deposited thin films reject ions and can potentially be utilized as nanofiltration membranes. By demonstrating the fabrication of these different classes of nanostructured materials, the advantages of pairing template synthesis with inkjet printing, which include fast and reliable deposition, judicious use of the deposited materials, and the ability to design chemically-patterned surfaces, are highlighted.