Fabrication of Photoluminescent Dyes/Poly(acrylonitrile) Coaxial Nanotubes Using Vapor Deposition Polymerization

Poly(acrylonitrile) (PAN) nanotubes with tunable wall thickness were successfully fabricated using a modified vapor deposition polymerization technique. To enhance the uniformity, heptane was employed as a nonreactive solvent. It is revealed that the heptane vapor in the reaction vessel plays an important role for producing nanotubes with tunable and uniform wall thickness. In addition, photoluminescence dyes such as pyrene for blue emission and rhodamine B for red emission were employed as host materials. These dyes were loaded into the inner surface of the PAN nanotubes and effectively encapsulated with a supplemental PAN layer. Confocal laser scanning microscopy images confirmed the successful fabrication of PAN−dye−PAN nanotubes without phase separation of the organic dyes. The photoluminescent analysis demonstrated the effective confinement of pyrene as well as rhodamine B in the PAN layer with a varying concentration of pyrene and rhodamine B as a multi-emission polymer nanotube.