One-Dimensional Arrangement of Gold Nanoparticles by Electrospinning

Abstract

The electrospinning technique was used successfully to fabricate one-dimensional arrays of Au nanoparticles within nanofibers in which the intrinsic nature of the semicrystalline polymer poly(ethylene oxide) (PEO) was employed as a template for the controlled nanoscale organization of nanoparticles. Differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy, UV-visible spectroscopy, scanning electron microscopy, atomic force microscopy, and transmission electron microscopy (TEM) were performed to characterize the resulting electrospun fibers in comparison with pure PEO and PEO/Au nanocomposite before electrospinning. By choosing chloroform as the solvent in this work the observed electrospun fibers were about 400-650 nm in diameter and revealed a well-defined Gaussian distribution. Thermal analysis showed that the dodecanethiol-capped Au nanoparticles preferentially act as heterogeneous nucleating agents for PEO crystallization. Conformational changes occurred by incorporating Au nanoparticles as well as electrospinning. The most common helical structure of PEO was transformed into a trans zigzag planar structure due to the high extensional flow caused by electrospinning. As a striking result, fairly long and one-dimensional chainlike structures consisting of Au nanoparticles within the electrospun fibers were observed by TEM. The present findings demonstrate that the electrospinning process provides not only a fundamental understanding of the conformational changes upon process conditions, but also a straightforward and cost-effective technique to fabricate one-dimensional arrays of nanoparticles for future nanodevices with unique properties in various applications, such as biological sensors, single-electron transistors, photonic materials, etc.

Formation and Characterization of Oriented Micro- and Nanofibers Containing Poly (ethylene oxide) and Pectin

“…In Figure 11d and 11e, the absorption peaks at 1625 cm −1 and 1730 cm The 1300 cm −1 to 800 cm −1 region presents characteristic bands that are unique to a compound, despite being usually difficult to interpret, and also correspond to the "fingerprint" of the polysaccharide molecules. 16 Moreover, as stated by Kim and co-workers: 17 r PEO is a semicrystalline polymer whose more thermodynamically stable structure at room temperature is a helical conformation. However, this structure can change under tension (resulting mostly likely in a planar zigzag conformation) or if water is added, which produces a triclinic crystalline structure.…”

Spectroscopy-based study on the interaction between gold nanoparticle and poly(vinylpyrrolidone) molecules in a non-hydrocolloid

“…Such effect arises when Au NPs are covered with a thin film of a dielectric material such as polymeric layer which helps in congregating n-electrons of PVP on the Au surface [13,22,40]. Again, such a large molar extinction coefficient (here, ε = 6.9 × 10 4 M −1 cm −1 ) is observed when PVP gets adsorbed on the surface of the NP and helps in altering the electronic properties of Au NPs by accumulating n-electrons of C=O moiety of PVP molecules on the Au surface in the Au-PVP nanocomposite [13,22,40]. The PVP solution is found to be totally transparent in the visible region (as shown in Figure 1 (a)).…”

Fabrication of Bio-Nanocomposite Nanofibers Mimicking the Mineralized Hard Tissues via Electrospinning Process

“…Although these nanocomposites exhibited high biocompatibility and improved mechanical properties with similar chemical composition to natural bone, they did not show any complex hierarchical nanostructures as bone. Recently, electrospinning technique has received a growing attention because polymer fibers prepared by this technique achieve fiber diameters in the range from micrometers down to a few nanometers straightforwardly and cost-effectively [21,22]. In a typical process, a polymer solution is forced through a capillary, forming a pendent drop at the tip of capillary.…”