Electrospinning of Flavin Mononucleotide-Functionalized Single-Walled Carbon Nanotubes

In this contribution, we describe the flavin mononucleotide (FMN) cofactor onto carboxylic functionalities of single-walled carbon nanotubes(SWNTs), using an electrospinning process to create the continuous nanoscale composite fibers from carbon nanotubes and polymer and FMN

Graphene Based Nanocomposite Hybrid Electrodes for Supercapacitors

There is an unmet need to develop high performance energy storage systems (ESS), capable of storing energy from both renewable and non-renewable sources to meet the current energy crisis and depletion of non-renewable sources. Amongst many available ESS, supercapacitors (ECs) are the most promising because they exhibit a high charge/discharge rate and power density, along with a long cycle life. The possibility of exploring the use of atomically thin carbon allotropes like graphene, carbon nanotubes (CNTs) and electrically conducting polymers (ECPs) such as polypyrrole (PPy) has been studied as a high performance conducting electrodes in supercapacitor application. A novel templated sustainable nanocomposite electrode has been fabricated using cellulose extracted from Cladophora c. aegagropila algae as component of the assembled supercapacitor device which later has been transitioned to a unique template-less freestanding nanocomposite supercapacitor electrode. The specific capacitance of polypyrrole-graphene-cellulose nanocomposite as calculated from cyclic voltammetry curve is 91.5 F g-1 at the scan rate 50 m Vs-1 in the presence of 1M NaCl electrolyte. The open circuit voltage of the device with polypyrrole -graphene-cellulose electrode was found to be around 225 m V and that of the polypyrrole -cellulose device is only 53 m V without the presence of graphene in the nanocomposite electrode. Understanding the fundamentals by fabricating template nanocomposite electrode, it led to fabricate a unique nanocomposite template-less freestanding film which comprises of polypyrrole-graphene-CNT hybrid. Various experiments have been performed using different electrolytes such ascorbic acid, sodium sulfate and sulfuric acid in different scan rates. The specific capacitance of polypyrrole-graphene-CNT nanocomposite with 0.1 wt% of graphene-CNT, as calculated from cyclic voltammetry curve is 450 F g-1 at the scan rate 5 m V s-1. For the first time a nanofibrous membrane has been developed as a separator which acts as an electrolyte reservoir and ionic diffusion membrane. The performance of the fabricated supercapacitor device has been analyzed using a multimeter and compared with a conventional alkaline (1.5 V) battery. Lighting up of 2.2 V light emitting diode has been demonstrated using the fabricated supercapacitor

Piezoelectric Materials Based Scaffolds Fabrication for Cardiamyocyets Cell Growth

Tissue engineering is concerned on the growth of tissue making organs for implantation back to the donor himself. Instead of using organs transplantation and expose the patient for immunological rejection possibility, implantation is another alternative approach. Artificial scaffolds have to be fabricated base on the targeted organ. The projected scaffolds should have designed shapes with a suitable mechanical toughness, wettability, porosity, biodegradability and biocompatibility. Ideally, the projected scaffold should also allow imitating of the normal cell microenvironment in order to produce a tissue with the same biological functions as found in a body. Cardiomyocytes or cardiac myocytes required specific type of scaffold and in this work we developed a pattern of polyvinylidene fluoride (PVDF), a piezoelectric, fluoropolymer, and a highly non-reactive using electro spinning to form a nanoscale fibers from a liquid as a concept of energy harvesting from heart beating using piezoelectric material. Three different polymer solutions were made using 15%, 12% and 10% of PVDF each in DMF under specific condition and quantities. The second part of this experimental work is to fabricate the PVDF nanofibers from polymer solutions in the presence of conductive graphene nanoplateletes under specific condition and quantities. All produced nanofibers will be characterized and compared using X-ray diffraction (XRD), Electrochemical Impedance Spectroscopy (EIS) and Dynamic Mechanical Analyzer (DMA) for choosing optimal fibers

Fabrication of Graphene Oxide Nanofibrous Thin Film using Electrojet Spraying

Graphene oxide (GO) is a promising material with excellent properties. The GO has an aromatic lattice sheets of graphene with multi oxygen functional groups, such as ketone, carboxyl, and carbonyl groups. The addition of these groups is resulting from an oxidation treatment of the graphene. Go has the ability to exfoliate in many solvents and disperse in the water. Hummers method is an improved way to synthesize the GO because no toxic gas forms in yield. It is a reversible material, so the graphite can be restored from the GO within electrochemical reduction. The advantage of the GO gives it the chance to take a part of various applications. The electrical and the mechanical are the main fields for the GO. Many groups made films and nanofibers of GO by using a combination of GO with other substances like, solvents or polymers to enhance the viscosity of the GO1. The aim of this work is to form the GO nanofibers from it owns film, which means self-assembly of the GO nanofibers. Furthermore, the GO which been used is pure. Two different techniques have been followed to overcome the viscosity issue of the GO. Electrospinning for the GO solution preformed as the first method. In this method the potential difference between the syringe and the collector causing an electric filed to draw the solution and form the fibers. The second method was vacuum filtration where the vacuum is used to absorb all the liquids and leave the GO over the filter to get fibers. These GO thin films can be used in plethora or applications such as energy storage, water and like solution filtration, oil and water separations and many more

Development of Electrochemical Sensors for the Detection of Trace Contaminants

Several industrial processes, such as stainless steel fabrication and textiles, produce heavy metal byproducts such as chromium. These heavy metals have detrimental effects on the surrounding environments and humans. Recently, electrochemical-driven sensors have been studied and show great potential in miniaturization while still providing measurements at a low cost. In addition, atomically thin allotropes of carbon, graphene, and graphene oxide have shown remarkable results in producing a highly responsive and selective sensor platform. These results are due to their excellent electrical conductivity, high surface area for utility, and physicochemical stability. The existing challenge for electrochemical-driven sensors is understanding the molecular level\u27s relationship between microstructures and chemical affinities. In this work, the research efforts are to understand the relation structure-property-function to comprehend reaction kinetics better and identify the rate-limiting steps. Experimental results from interdigitated micro-comb chips deposited with nanocomposite electrodes will be presented under different electrolytes and varying concentrations. In addition, we will display governing mechanisms of charge transfer relating to sensor performance

Energy Storage using Graphene-Polymer nanocomposite thin film

There is an unmet need for efficient and environmentally-friendly ultrathin energy storage devices. Here we report a thin and flexible energy storage mechanism using electrically conductive polymer (ECPs) polypyrrole and atomically thin material and a highly conductive allotrope of carbon graphene which is coated on thin paper substrate made from cladophora aegagropila algae cellulose. The cyclic voltammetry data exhibits a capacitive behavior of the device, as do the multimeter readings of the voltage while charging and discharging exhibit a battery performance. The device demonstrated hybrid characteristics in which graphene behaved as an electrochemical double layer capacitance (EDLC) and PPy behaved as a pseudo-capacitor. With significant mechanical strength and flexibility, the device shows good power density, higher charge discharge cycles, and lower self discharge rates. TEM and SEM images show well dispersion of graphene on the surface of cellulose fibers. In order to decrease the effective weight of the insulating material and to achieve a controlled thickness of the electrode in few microns to nm range we propose the fabrication of the thin film using electrodeposition technique. Preliminary experiments show that using a small electrode of 1cm2 area we can achieve up to 1.5 V of potential across the terminal

Polyfiberquant software tool for cell state prediction

According to WHO, non-communicable diseases (NCDs) were responsible for 68% of all deaths globally in 2012, up from 60% in 2000. The four main NCDs are cardiovascular diseases, cancers, diabetes and chronic lung diseases. In most of the diseases, morphological and / or functional characteristics of cell facilitate researchers and clinicians to determine the cell state (i.e. diseased or healthy, disease state, etc). In recent years, high-resolution imaging approaches (ex. confocal microscopy) are used to study and understand the morphological characteristics of the cell.  In addition, there are few computational tools developed to process these high-resolution imaging images to identify the cell state. Polyfiberquant is one of the unique  software tool for cell state prediction. But the sensitivity and specificity of the tool is primarily dependent on the parameters used in the prediction.  Therefore, the primary goal of this study is to find the best parameters that can be used in Polyfiberquant tool that result in reliable cell state prediction using confocal microscopy images. Secondarily, the study will also determine the limitations of this tool

NMR detection of graphene nanoribbons

Nobel prize winning material as "the thinnest material in our universe", graphene, a single atom thick sheet of sp2 carbon atoms, promises a diverse range of applications from composite materials to quantum dots, and even in several bioengineering applications. For graphene, that availability is encumbered by having to surmount the high cohesive van der Waals energy (5.9 kJ mol-1 carbon) adhering graphitic sheets to one another. Moreover, graphene being extremely hydrophobic, it has low solubility in water. Here we demonstrate the feasibility of developing biological graphene dispersions using wet chemistry and ultra sonication. 13C NMR spectra of graphene dispersions indicate the presence of graphene carbon signature in solution. Our future work is to use this graphene dispersion in a cellular assay to explore graphene-protein binding and also to study the graphene nanoribbon structures as contrast agents and drug delivery

Role of Alloy Oxidation on Performance of Solid Oxide Fuel Cells for Clean Energy Generation

As the global demand for electricity grows, the need to lower carbon emissions become increasingly important. To face this challenge many research and development projects have explored alternative sources of clean energy to integrate into existing energy infrastructure. One such alternative is solid oxide fuels cells (SOFCs) which have emerged as a potential energy conversions system using fuels such as hydrogen for its power generation processes. Electrochemical reaction between hydrogen and oxygen from the air generates electricity, producing water (H2O) as the by-product. Typically operating within a temperature range of 500-900°C, SOFCs can regularly produce power without the need for revitalization if the fuel supply is maintained. A metallic interconnect (IC) is used on both cathode and anode electrodes, serving as a current collector and as a gas manifold to deliver gases to both electrodes. The oxidation behavior of these alloys has a significant impact on the electrical properties of oxide scales under the complex operating atmosphere of SOFCs. This work will investigate the role of different alloys and their oxidation behavior as a function of time and temperature on performance of SOFC cells. The effects on area specific resistance (ASR) measured under high temperature will be studied. The implications of alloy oxidation and corrosion under systems operating conditions will also be investigated. Additionally, their effects on the conductive pathway in an electrochemical cell will be discussed. The findings relating to this research have potential applications in energy storage and conversion for transportation, residential, and commercial systems

Analyzing structural DNA binding with nanoparticles for gene therapy

The study of DNA binding with nanoparticles and their packaging assembly is an essential requirement for gene therapy. The structural features of DNA and nanoparticles would be very useful in development of novel gene therapy in genes. Plants being good test system as they are tolerant of being bombarded with small particulates and usually grow normally even after such treatments. We used primers from plant named "Frigida"