Search results for "Nanofiber"

Electrospun nanofibers: role of nanofibers in water remediation and effect of experimental variables on their nano topography and application process…

2021

Water is the elixir of life and the most elementary need for the survival of human beings on planet Earth. With rapid industrialization, globalization and human exploitation, natural water resources are diminishing at a startling rate wherein availability of potable water has drastically decreased in recent times and hence membrane technology is a highly pursued area for water purification. The simple and cost-effective electrospinning technique has evolved to be a state-of-the-art method for developing nanofibers of tailored thickness and diameters by combining a broad range of starting materials. This comprehensive review emphasizes on the demonstration of electrospun nanofibers based on …

Theoretical and practical aspects of chemical functionalization of carbon nanofibers (CNFs): DFT calculations and adsorption study

2011

The nitric acid-functionalized commercial carbon nanofibers (CNFs) were comprehensively studied by instrumental (XRD, BET, SEM, TGA) and theoretical (DFT calculations) methods. The detailed surface study revealed the variation in the characteristics of functionalized CNFs, such as a decreased (up to 34%) surface area and impacted structural, electronic and chemical properties. The effects of functional groups were studied by comparison with pristine nanofibers. The results showed that the C-C bond lengths of the modified CNFs varied significantly. Chemical functionalization altered the frontier orbitals of the pristine material, and therefore altered the nature of their interactions with ot…

High throughput electro-hydrodynamic processing in food encapsulation and food packaging applications: Viewpoint

2017

Abstract Looking genuinely at nature, nanofibers often serve as a basic platform where either organic or inorganic components are built upon. The fiber structure exhibits, from a structural point of view, the intrinsic ability to mechanically reinforce materials but also the less well-known property of enhancing the barrier performance of polymer matrices when applied smartly. To reproduce and tailor this extraordinary nature's design, a reliable technology that is able to fabricate fiber nanostructures from a variety of materials with size and size distribution control and composition flexibility is highly desirable. In addition, if this technology could allow nanofiber shortening to achie…

Probing Laser Plasma Dynamics Using High-Order Harmonics Generation in Carbon-Containing Nanomaterials

2021

We study high-order harmonics generation from plasmas generated from graphite, fullerenes, carbon nanotubes, carbon nanofibers, diamond nanoparticles, and graphene. Our approach utilizes a heating nanosecond laser pulse to produce plasmas that serve as the media for high harmonic generation from a subsequent driven femtosecond laser pulse. High harmonics are generated at different time delays following the plasma formation, which allows us to analyze the spreading of species with different masses. We analyze the harmonic yields from species of single carbon atom, 60 atoms (fullerene), 106 atoms (diamond nanoparticles), 109 atoms (CNTs and CNFs), and even much larger species of graphene shee…

The diffusion of carbon atoms inside carbon nanotubes

2008

We combine electron irradiation experiments in a transmission electron microscope with kinetic Monte Carlo simulations to determine the mobility of interstitial carbon atoms in single-walled carbon nanotubes. We measure the irradiation dose necessary to cut nanotubes repeatedly with a focused electron beam as a function of the separation between the cuts and at different temperatures. As the cutting speed is related to the migration of displaced carbon atoms trapped inside the tube and to their recombination with vacancies, we obtain information about the mobility of the trapped atoms and estimate their migration barrier to be about 0.25 eV. This is an experimental confirmation of the remar…

Carbon Nanotubes: In-Situ Growth of Ultrathin Films of NiFe-LDHs: Towards a Hierarchical Synthesis of Bamboo-Like Carbon Nanotubes (Adv. Mater. Inter…

2014

Solid-State Pyrolyses of Metal Phthalocyanines: A Simple Approach towards Nitrogen-Doped CNTs and Metal/Carbon Nanocables

2006

Solid-state pyrolysis of organometallic precursors has emerged as an alternative method for preparing carbon nanostructures such as carbon nanotubes (CNT) and carbon anions. The morphology of the tubes can be controlled by the nature of the precursors and the pyrolysis procedures, and micrometer long nanotubes, composed of metal carbide wires encased in a graphitic sheath. Cobalt phthalocyanine (CoPc) as well as iron phthalocyanine were pyrolyzed at different temperatures to obtain CNTs. HRTEM and energy-dispersion X-Ray analysis disclosed that the core consisted of long, iron-containing single crystals and that the core was fully surrounded by crystallized graphic carbon. Iron-filled carbo…

Poly-l-Lactic Acid Nanofiber-Polyamidoamine Hydrogel Composites: Preparation, Properties, and Preliminary Evaluation as Scaffolds for Human Pluripote…

2016

Electrospun poly-l-lactic acid (PLLA) nanofiber mats carrying surface amine groups, previously introduced by nitrogen atmospheric pressure nonequilibrium plasma, are embedded into aqueous solutions of oligomeric acrylamide-end capped AGMA1, a biocompatible polyamidoamine with arg-gly-asp (RGD)-reminiscent repeating units. The resultant mixture is finally cured giving PLLA-AGMA1 hydrogel composites that absorb large amounts of water and, in the swollen state, are translucent, soft, and pliable, yet as strong as the parent PLLA mat. They do not split apart from each other when swollen in water and remain highly flexible and resistant, since the hydrogel portion is covalently grafted onto the …

Synthesis and characterisation of ordered arrays of mesoporous carbon nanofibres

2009

A facile and reproducible one-step pathway has been developed for preparing ordered arrays of mesoporous carbon nanostructures within the pores of anodized aluminium oxide (AAO) membranes, through the confined self-assembly of phenol/formaldehyde resol and amphiphilic copolymer templates. The morphology of the mesoporous carbon nanostructures can be controlled by varying the copolymer surfactant, the quantity of the resol–surfactant precursor sol used and the amount of phenol–formaldehyde resol introduced into the resol–surfactant sol. One-dimensional (1-D) carbon nanostructures, such as carbon fibres with a core–shell structure and carbon ribbons with circular mesopores running parallel to…

Properties-morphology relationships in electrospun mats based on polylactic acid and graphene nanoplatelets

2018

Abstract Aligned and randomly oriented polylactic acid (PLA) biocomposite nanofiber mats filled with Graphene nanoplatelets (GnP) were prepared by electrospinning. The morphological analysis revealed the successful alignment of the fibers achieved by collecting the mats on a high-speed rotary drum. Furthermore, GnP addition on the polymeric solution leads to an increase of the viscosity with a consequent increment of the fiber diameter. Tensile tests demonstrated that the reinforcing effect of GnP when added to the PLA matrix was more than three times higher in the aligned systems if compared with the respective randomly oriented mats. DSC analysis showed that GnPs were able to slightly inc…