Flexible janus nanofibers: Facile electrospinning construction and enhanced luminescent-electrical-magnetic trifunctionality

Abstract

Flexible luminescent-electrical-magnetic trifunctional Janus nanofibers have been successfully fabricated through electrospinning technology by using specially designed parallel spinnerets. The terbium complex [Tb(ba) 3(phen)] (BA=benzoic acid, phen=1,10-phenanthroline), polyaniline (PANI), and Fe3O4 nanoparticles (NPs) were incorporated into polyvinyl pyrrolidone (PVP) and electrospun into Janus nanofibers with [Tb(ba)3(phen)]/PVP as one strand of the nanofiber and PANI/Fe 3O4/PVP as another. The morphologies and properties of the final products were investigated in detail by XRD, SEM, TEM, fluorescence spectroscopy, Hall effect measurement system, and vibrating sample magnetometry. The [[Tb(ba)3(phen)]/PVP]//[PANI/Fe3O4/PVP] Janus nanofibers, with an average diameter of 180 nm, simultaneously possess enhanced luminescent performance, electrical conduction, and magnetism. Fluorescence emission peaks of Tb3+ are observed in the [[Tb(ba) 3(phen)]/PVP]//[PANI/Fe3O4/PVP] Janus nanofibers and assigned to the 5D4→5F 6 (λ=491 nm), 5D4→ 5F5 (λ=544 nm), 7D4→ 5F4 (λ=585 nm), and 5D 4→7F3 (λ=620 nm) energy-level transitions of Tb3+ ions; the 5D4→ 5F5 hypersensitive transition at λ=544 nm is the predominant emission peak. The electrical conductivity of Janus nanofibers reaches up to the order of 10-3 Scm-1. The luminescent intensity, electrical conductivity, and magnetic properties of Janus nanofibers can be tunable by adjusting the amounts of rare-earth complex, PANI, and Fe 3O4 NPs present. This new type of luminescent-electrical- magnetic trifunctional Janus nanofiber holds potential for a variety of applications, including molecular electronics, microwave absorption, and future nanodevices, owing to their excellent fluorescence, electrical conduction, and magnetism. Two-faced fibers: Flexible Janus nanofibers with enhanced luminescent-electrical-magnetic trifunctionality have been successfully fabricated (see picture). The unique structure allows the isolation of Fe 3O4 nanoparticles (NPs) and polyaniline (PANI) from [Tb(ba)3(phen)] (ba=benzoic acid, phen=1,10-phenanthroline), resulting in weaker light absorption of Fe3O4 NPs and PANI, and strong luminescence of the nanofibers. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.