| 1. |
- Afroz, Laila, et al.
(author)
-
Nanocomposite Catalyst (1 – x)NiO-xCuO/yGDC for Biogas Fueled Solid Oxide Fuel Cells
- 2023
-
In: ACS Applied Energy Materials. - : American Chemical Society (ACS). - 2574-0962. ; 6:21, s. 10918-10928
-
Journal article (peer-reviewed)abstract
- The composites of Ni–Cu oxides with gadolinium doped ceria (GDC) are emerging as highly proficient anode catalysts, owing to their remarkable performance for solid oxide fuel cells operated with biogas. In this context, the nanocomposite catalysts (1 – x)NiO-xCuO/yGDC (x = 0.2–0.8; y = 1,1.3) are synthesized using a solid-state reaction route. The cubic and monoclinic structures are observed for NiO and CuO phases, respectively, while CeO2 showed cubic fluorite structure. The scanning electron microscopic images revealed a rise in the particle size with an increase in the copper and GDC concentration. The optical band gap values are calculated in the range 2.82–2.33 eV from UV–visible analysis. The Raman spectra confirmed the presence of vibration modes of CeO2 and NiO. The electrical conductivity of the nanocomposite anodes is increased as the concentration of copper and GDC increased and reached at 9.48 S cm–1 for 0.2NiO-0.8CuO/1.3GDC composition at 650 °C. The electrochemical performance of (1 – x)NiO-xCuO/yGDC (x = 0.2–0.8; y = 1,1.3)-based fuel cells is investigated with biogas fuel at 650 °C. Among all of the as-synthesized anodes, the fuel cell with composition 0.2NiO-0.8CuO/1.3GDC showed the best performance, such as an open circuit voltage of 0.84 V and peak power density of 72 mW cm–2. However, from these findings, it can be inferred that among all other compositions, the 0.2NiO-0.8CuO/1.3GDC anode is a superior combination for the high electrochemical performance of solid oxide fuel cells fueled with biogas.
|
|
| 2. |
|
|
| 3. |
- Asadi, Milad, 1987-, et al.
(author)
-
Microfabrication of conjugated polymer actuators on textiles and study of textile structures for scaling up the actuation
- 2019
-
Conference paper (peer-reviewed)abstract
- Conjugated polymers have been developed over the last decade for applications as artificial muscle. These polymers can be synthesized on the conventional yarns to prepare actuators. When a single yarn is functionalized with such polymers, the isotonic generated strain is very low (around 0.075%). In order to reach the early stages of commercialisation, especially in exo-skeleton devices, it is critical to amplify the actuation mechanism in both isometric force transfer and strain generation. In our previous study we showed that by using a 2´1 rib knitted fabric as a viscoelastic substrate, the generated strain enhances to 3%.However, viscoelastic properties of fabrics are determined not only by the constitutive operators of the fibers but also by the fabric pattern and its structures, which governs the fibre deformation. Here we have studied the actuation mechanism of polypyrrole on various fabric structures.Polyamide 6 and stretchable polyamide 6/PU fibers were used to knit the fabrics. Fabrics were pre-modified with tannic acid and bath sonicated for its stress relaxation. Then, they were dip-coated in PEDOT:PSS solution in order to achieve an electrode layer. Dynamic elastic behaviour of samples was measured before and after applying the seed layer. Further, electrochemical synthesis of polypyrrole on PEDOT:PSS was taken place by a 3-electrode electrochemical cell setup. A dual-mode muscle lever was used to characterize the textile actuators. The results show that the efficiency of actuation mechanism is determined by both viscoelastic properties and stress-relaxation time of textiles.
|
|
| 4. |
- Bashir, Tariq, 1981-, et al.
(author)
-
Cellulosic Smart Textile Fibers based on Organic Electronics
- 2016
-
Conference paper (peer-reviewed)abstract
- The paradigm shift of merging structural properties of materials with other functionalities prevails and cellulose based fibres are no exception. For the realisation of so called smart materials, including smart textiles, electrical conductivity is of special importance, enabling sensorics, signal transmission, energy supply, energy generation, and actuation. We here discuss taking use of the advancement within the organic electronics community of conjugated polymeric systems producing smart textile fibres for inclusion into garment as well as interior and technical textiles. Specifically, poly(3,4-ethylenedioxythiophene) known as PEDOT is studied as a model system. PEDOT has relevance being a working horse within the organic electronics community. Our emerging pilot line is based on creating conductivity by vapour polymerization of EDOT monomers on an oxidant coated textile fibre where these could be taken from arrange of materials. Here we focus on cellulose based fibres. It is shown that Tencell-Lyocell is a suitable substrate offering many anchoring sites and that multiple depositions with layers deposited directly on each other decreased the resistance from 5.1 (± 1.6) kΩ/10 cm to 1.0 (± 0.1) kΩ/10 cm, for one layer and multiple layers respectively. Furthermore, adding 15 wt. % of the copolymer PEG-PPG-PEG to the oxidant solution decreased the resistance from 6.8 (± 1.2) kΩ/10 cm to 3.9 (± 0.8) kΩ/10 cm.
|
|
| 5. |
- Bashir, Tariq, 1981-, et al.
(author)
-
High-strength electrically conductive fibers: functionalization of polyamide, aramid and polyester fibers with PEDOT polymer
- 2017
-
In: Polymers for Advanced Technologies. - : John Wiley & Sons. - 1042-7147 .- 1099-1581. ; 29:1, s. 310-318
-
Journal article (peer-reviewed)abstract
- In this work, high-performance fibers such as aramid (Twaron), polyamide (PA6), polyester (PET), and hybrid Twaron/PA6 fibers were transformed into electroactive fibers by coating them with conjugated polymer, poly(3,4-ethylenedioxythiophene) (PEDOT) through vapor phase polymerization (VPP) method. The VPP is considered as an efficient technique for depositing CPs on different substrates regardless of their lower solubility in various solvents. In this paper, PEDOT-coated high-performance fibers were prepared under already optimized reaction conditions, and then a comparison between electrical, thermal, and mechanical properties of different fibers, before and after coating, was made. The obtained coated fibers were characterized through scanning electron microscope (SEM), thermogravimetric analysis (TGA), 2-probe electrical resistance measurement method, and tensile testing. It was revealed that at particular reaction conditions, all high performance textile substrates were successfully converted into electroactive fibers. The voltage-current (V-I) characteristics showed that PEDOT-coated polyester fibers exhibited highest conductivity value among all other substrate fibers. The active PEDOT layers on high performance fibers could behave as an antistatic coating to minimize the risks associated with static charges at work places. Also, the obtained fibers have potential to be used as smart materials for various medical, sports, and military applications.
|
|
| 6. |
- Dutta, Sujan, et al.
(author)
-
Textile Actuators Comprising Reduced Graphene Oxide as the Current Collector
- 2023
-
In: Macromolecular materials and engineering. - : WILEY-V C H VERLAG GMBH. - 1438-7492 .- 1439-2054.
-
Journal article (peer-reviewed)abstract
- Electronic textiles (E-textiles) are made using various materials including carbon nanotubes, graphene, and graphene oxide. Among the materials here, e-textiles are fabricated with reduced graphene oxide (rGO) coating on commercial textiles. rGO-based yarns are prepared for e-textiles by a simple dip coating method with subsequent non-toxic reduction. To enhance the conductivity, the rGO yarns are coated with poly(3,4-ethylene dioxythiophene): poly(styrenesulfonic acid) (PEDOT) followed by electrochemical polymerization of polypyrrole (PPy) as the electromechanically active layer, resulting in textile actuators. The rGO-based yarn actuators are characterized in terms of both isotonic displacement and isometric developed forces, as well as electron microscopy and resistance measurements. Furthermore, it is demonstrated that both viscose rotor spun (VR) and viscose multifilament (VM) yarns can be used for yarn actuators. The resulting VM-based yarn actuators exhibit high strain (0.58%) in NaDBS electrolytes. These conducting yarns can also be integrated into textiles and fabrics of various forms to create smart e-textiles and wearable devices.
|
|
| 7. |
-
Graphene-modified E-textiles: An industry relevant approach of doping and visualizing fully textile P-N junction diodes
- 2020
-
Editorial proceedings (pop. science, debate, etc.)abstract
- Recently, graphene has been used to obtain (E)-textiles. From an industry-relevant perspective, it is essential to introduce a process that could be scaled-up. We applied a cost-effective dip-coating method using bio-sourced agents for chemical adsorption of graphene oxide (GO). Polyester and viscose woven fabrics were treated with an aqueous solution of glycerol (4 g.L-1) to overcome the electrostatic repulsion among fibers and GO and then dip-coated with a dispersion of GO. The results are homogeneous GO coating with one to a few layers of GO nano-sheets. Further, The GO was chemically reduced to rGO, by using tannic acid (10 g.L-1) as a bio-sourced reducing agent. This brings electrical conductivity to rGO nano-sheets having an electrical resistance of 2±1 and 10±4 kΩ/sq for polyester and viscose fibers respectively. Afterward, these E-textiles are both p-type and n-type doped, using nitrogen plasma treatment to prepare nitrogen-doped graphene as a p-type E-textile and electrochemical deposition of titanium on graphene as n-type Doped E-textiles. This increases the charge carrier density, consequently increasing the conductivity of the graphene. Doping rGO-modified textiles open up a visualization of the p-n junction fully-textile diodes and its further applications.
|
|
| 8. |
- Guo, Li, et al.
(author)
-
Electroconductive textiles and textile-based electromechanical sensors — integration in as an approach for smart textiles
- 2016. - 1
-
In: Smart Textiles and their Applications. - : Woodhead Publishing Limited. - 9780081005743 ; , s. 657-693
-
Book chapter (peer-reviewed)abstract
- The unification of textiles and electrics opens up many interesting possibilities for sensorics, actuation, energy transport, energy storage, and information transport. Electrics need conductive structures. Industrially knittable and weavable filaments and yarns are in this chapter overviewed in a typology of seven classes. These are the basics for the integration in approach that is put forward as a concept for successful production of smart textiles.Integration means that a "device" is (1) made by a textile production process and (2) made as a textile. We focus on smart textiles for mechanical sensoring that give an electrical output as these embrace such basic quantities as position, movement, speed, acceleration, elongation, forces, pressure, and vibration. Cases of mechanical sensors are demonstrated based on piezoelectricity and capacitive techniques. It is shown that these are promising technologies for smart textiles in general and the integration approach specifically.
|
|
| 9. |
- Huniade, Claude, 1996-, et al.
(author)
-
A pilot line to functionalise textile fibres for textile actuators
- 2023
-
Conference paper (peer-reviewed)abstract
- Textile actuators are at their infancy within the field of electromechanically active polymers. Crude fabric coatings as well as coated pieces of yarns can certainly perform actuation. However, they do not fully consider the capabilities of textile processes and structures. To allow for such possibilities, it is required to have a sufficient supply of processable functional fibres. The presented pilot line is designed to produce said functional fibres from commercial textile yarns. The three continuous processes composing the pilot line are: the layered dip coating using a PEDOT:PSS based solution, the electrodeposition of polypyrrole (PPy) onto the PEDOT coated fibres, and the ultraviolet cured dip coating of ionogels (i.e. dipping followed by UV curing). The continuous aspect of the processes is a key element for fabric manufacturing. Indeed, even the smallest usable fabric requires a substantial length of yarn. This is one of the reasons why the produced fibres were tested on an industrial knitting machine, the other reason being to test their processability. Additionally, a series of tests have been done on the fibres to obtain their conductive, tensile and, if applicable, actuative properties. Therefore, we present a pilot line producing knittable PEDOT coated fibres, textile muscle fibres and ionofibres.
|
|
| 10. |
- Huniade, Claude, 1996-, et al.
(author)
-
Disposable, green smart textiles based on conductive graphite fibres
- 2019
-
Conference paper (other academic/artistic)abstract
- Smart textiles, a part of the present boom of wearables, is at the risk of being a newenvironmental problem as many axioms of sustainability are violated here, that of driving(mass) consumption, mixing of components of different material origin and no obvious wastehandling system when used and worn out. Smartness has been synonymous with integration ofelectronic conductivity functionality, typically realised by metal wires. Carbon allomorphsshowing low electrical resistivity might be an environmental friendly alternative.Here we report on attempts with simple conductive graphite systems from which we makeconductive textile fibres, the production of which could be up-scaled to industrial volumes.Coating textile bulk fibers as polyester, polyamide, wool and cellulose based regenerate onesrather than (melt/wet) spinning new fibers, the mechanical properties are sustained makingthem processable within existing textile processes infrastructure.Several different graphite compositions and different yarn topologies are compared. Twisting isshown to greatly increase the overall yarn conductance. Fabrics are manufactured with thegraphite yarns in the double role of being structural as well as functional. Furthermore, analphabet of fundamental electrical circuitry elements are demonstrated; conductor, capacitor,inductor. The devices are consisting of non-toxic components that are disposable andcompostable; showing the benefits of carbon based soft electronics.
|
|
| 11. |
- Huniade, Claude, 1996-, et al.
(author)
-
EMIm-OTf Ionogel Coated Fibres - Characterisation and Development, Aiming at Ionic Smart Textiles
- 2021
-
Conference paper (other academic/artistic)abstract
- Ions are prevalent within bioelectronics, as they are the main charge carriers in living systems. In contrast to electronic systems, ionic ones are closer to what can be found in our body; in muscles, neurons and nerves.Textiles are a much-used biomedical material, both in vivo and in vitro due to its membrane character, highly efficient area, softness, biocompatibility and biodegradability. Modifying the physicochemical properties of the core or the surface of textile has been reported a countless number of times, but still, its use in a bioelectrical context is limited.Fibres are the building blocks of textiles and what make textiles an architected class of material. Then ionically conductive fibres are of great interest.Here, we show the preparation of iono-conductive textile fibres through the (semi-)continuous dip-coating of ionogel on the cellulose-based viscose.Ionogels are composed of salts in liquid state and a 3-dimensional solid network, in our case an ionic liquid (IL), 1-Ethyl-3-methylimidazolium trifluoromethanesulfonate, commonly named EMIm OTf or EMIm Triflate, and a thiol acrylate network, allowing the mobility of the ions within or in/out of the gel. This specific combination is a first effort towards the development of ionic textile fibres and ionic smart textiles, as a variety of ILs with different cations and anions exists, potentially allowing a large number of different combinations.We investigate how the coating of this ionogel affects the mechanical properties as well as the conductivity in AC or DC arrangement and their relation to temperature and humidity. Also, the thermal stability and sensitivity of degradation of the fibre system is studied.Moreover, we introduce different textile structures, and potential applications directed to bioelectronics.
|
|
| 12. |
- Huniade, Claude, 1996-, et al.
(author)
-
Investigating ionic liquid-based click-ionogels by thiol-ene photopolymerisation onto textile yarns/fibres
- 2021
-
Conference paper (other academic/artistic)abstract
- Electronic textiles’ primordial component are the connections that allow a circuit to be formed. As for today, the catalogue of conductive yarns is expanded to highly conductive metals such as copper, silver and steel, or electroconductive plastics composed of conductive polymers and electroconductive fillers such as metal particles or carbon allotropes.Ionic liquids are also able to carry electrical charges, and their capacity to conduct electricity has yet to be investigated as a yarn component, e.g. an ion conducting coating.Here, we report on attempts to coat ionic liquid-based click-ionogel on fibres, using thiol-ene reactions with the help of a photobase generator.Ionogel precursors, composed of plurithiol precursors, acrylate monomers and a triflate ionic-liquid, are applied on yarn and then cured by UV irradiation, initiating the Michael reaction and creating the thiol-acrylate-triflate network around the yarn.The aim of the present study is to prepare and characterise yarns coated with such ionogels, while developing a continuous yarn coating process.Several different ionogel compositions and different yarn topologies are investigated, comparing their structure, electrical conductivity, mechanical properties, thermal stability, behaviour to chemical reagents, as well as the different surface tensions and interfacial interactions.Textile processability is explored by the manufacture of simple fabrics.An application for those ionic conductive coating is the ion supply for electroactive polymers coated yarns that currently rely on electrolytes. This novel coating will render the light-weight property of textile valuable, and therefore broadening their application as wearables.
|
|
| 13. |
- Huniade, Claude, 1996-, et al.
(author)
-
Ionofibers: Ionically Conductive Textile Fibers for Conformal i-Textiles
- 2022
-
In: Advanced Materials Technologies. - : Wiley. - 2365-709X.
-
Journal article (peer-reviewed)abstract
- With the rise of ion-based devices using soft ionic conductors, ionotronics show the importance of matching electronic and biological interfaces. Since textiles are conformal, an essential property for matching interfaces, light-weight and comfortable, they present as an ideal candidate for a new generation of ionotronics, i-textiles. As fibers are the building blocks of textiles, ionically conductive fibers, named ionofibers, are needed. However, ionofibers are not yet demonstrated to fulfill the fabric manufacturing requirements such as mechanical robustness and upscaled production. Considering that ionogels are known to be conformal films with high ionic conductivity, ionofibers are produced from commercial core yarns with specifically designed ionogel precursor solution via a continuous dip-coating process. These ionofibers are to be regarded as composites, which keep the morphology and improve the mechanical properties from the core yarns while adding the (ionic) conductive function. They keep their conductivity also after their integration into conformal fabrics; thus, an upscaled production is a likely outlook. The findings offer promising perspectives for i-textiles with enhanced textile properties and in-air electrochemical applications.
|
|
| 14. |
- Kalantar Mehrjerdi, Adib, 1965-, et al.
(author)
-
Melt rheology and extrudate swell properties of talc filled polyethylene compounds
- 2020
-
In: Heliyon. - : Elsevier. - 2405-8440.
-
Journal article (peer-reviewed)abstract
- An experimental study of high-density polyethylene (HDPE) composites filled with talc (0–15 wt.%) was carried out to investigate the rheological properties. The apparent melt viscosity, melt density, and die-swell ratio (B) of the composites were measured at constant shear stress and constant shear rate by using a melt flow indexer and capillary rheometer. The experimental conditions were set to a temperature range from 190 to 220 C for both apparatuses whereas a load range from 5 to 12.16 kg was selected for melt flow indexer and shear rate range from 1 to 10000 s1 for capillary rheometer. The initial study showed that the talc particulates did not influence the melt viscosity compared with the neat HDPE but decreased the elasticity of the polymer system. The HDPE/talc systems obeyed power-law model in shear stress–shear rate variations and were shear thinning, meanwhile, the die-swell increased with an increased wall shear rate and shear stress. The melt density of the composites increased linearly with an increase of the filler weight fraction and decreased with the increase of the testing temperature. The talc-HDPE composites showed compressible in the molten state.
|
|
| 15. |
- Miankafshe, Milad Asadi, et al.
(author)
-
Electrostatic grafting of graphene onto polyamide 6,6 yarns for use as conductive elements in smart textile applications
- 2020
-
In: New Journal of Chemistry. - : Royal Society of Chemistry. - 1144-0546 .- 1369-9261. ; 44:18, s. 7591-7601
-
Journal article (peer-reviewed)abstract
- Electrostatic graphene-grafted conductive yarns were prepared based on a scalable manufacturing method using conventional polyamide 6,6 (PA 6,6) multifilament yarns, common in the textile industry. Graphene oxide (GO) shows negative surface charge at any pH and PA 6,6 has an isoelectric point (IEP = pH|(zeta=0)) of 3.6. When GO and a polymer have the same charge sign, the resulting electrostatic interaction is repulsive and an electrostatic attraction does not arise until the polymer backbone has an oppositely charged sign compared to the GO nanosheets. To achieve this, yarns were modified with protonated chitosan (CS) followed by dip-coating with GO, resulting in electrostatic grafting of oxygen functional groups of GO onto amino groups of CS polymer chains. This coating process provides durable electrically conductive yarns (3 x 10(-2) to 4 x 10(-2) S m(-1)) with an excellent fastness to washing. It leads to the realization of graphene-grafted yarns as building elements of smart textiles, obtaining metal-free textile sensors. These yarns are capable of supplying power to an LED light using a 9 V battery and are expected to be an excellent candidate for feeding V-bed flat-knitting, Jacquard and raschel knitting machines. To achieve this, a wearable tactile sensor was designed and prepared using a flat-knitting machine and the sensor was characterized through electrical, mechanical, and electromechanical measurements.
|
|
| 16. |
- Milad, Asadi Miankafshe, 1987-, et al.
(author)
-
The role and importance of surface modification of polyester fabrics by chitosan and hexadecylpyridinium chloride for the electrical and electro-thermal performance of graphene-modified smart textiles
- 2019
-
In: New Journal of Chemistry. - : Royal Society of Chemistry (RSC). - 1144-0546 .- 1369-9261. ; 17:43, s. 6643-6658
-
Journal article (peer-reviewed)abstract
- Graphene has the potential to create highly valuable electrical conductive textile systems with maintained pliability and psychological comfort. There have already been numerous studies regarding electrically functionalized graphene-coated textiles. However, processing development is far from being exhausted. Here we have studied electro-thermal textiles based on the most common fibers, polyester, and an industry-relevant graphene impregnation method by introducing surface pre-modification of fabrics for graphene-modified textile processing. For this purpose, polyester fabrics were treated with four different cationic agents and impregnated with graphene oxide (GO) colloidal particles. Then, direct chemical reduction of GO to an electrically conductive graphene oxide (rGO) was performed. A pristine fabric modified by rGO showed a high resistance of 27.3 kΩ □−1 without any electro-thermal activity, whilst chitosan-treated (CS) and hexadecylpyridinium chloride-treated (HDPC) fabrics had resistance values of 2.7 and 0.59 kΩ □−1 respectively, and excellent heat propagation with a good temperature distribution. The steady-state temperature of CS-treated and HDPC-treated fabrics increased from 28 °C and 33 °C to 60 °C and 120 °C, respectively, as the voltage applied increased from 10 V to 30 V. These rGO-modified fabrics also have excellent electro-mechanical performance, and are good candidates for flexible strain sensor applications.
|
|
| 17. |
- Milad, Asadi Miankafshe, 1987-, et al.
(author)
-
The role and optimization of cationic agents for adhesion and electrical conductivity of graphene-coated e-textiles
- 2018
-
Conference paper (pop. science, debate, etc.)abstract
- Textiles with electrical properties, known as e-textiles, are realized by different methods. Among these, graphene-coated textiles have attracted great attention due to its multifunctional properties such as being flexible lightweight; and offering interesting optical and electrical properties. While Aqueous dispersion of graphene oxide (GO) could be prepared and applied as a dye to textiles via a simple and cost-effectivene dip-coating method. Moreover, the GO could be reduced to graphene directly on the surface of the textiles. However, the GO flakes do not adhere properly to most textiles at any pH values probably because of electrostatic repulsion between the particles and the textile substrate as both the aqueous solution of GO and most textiles carry negative surface charges. Though, GO flakes could be easily assembled on a positively charged surface. Therefore, textiles need to be cationized before the dip-coating in the GO dispersion. In this work a number of both organic and inorganic cationic agents such as chitosan, Poly(diallyldimethylammonium chloride), Hexadecylpyridinium chloride, and Polyethylenimine are applied to the textiles before the coating process. Further on the so formed systems are characterized by scanning electron microscopy, FT-IR measurement, four-terminal sensing surface resistance measurement, diffusion reflection spectroscopy, electro-thermal analysis, and electro-mechanical analysis. The results display the fact that utilizing an appropriate cationic agent not only enhances the absorption of GO onto the textile surfaces but also play a critical role for the electrical conductivities and electro-thermal properties of the coated fabrics, with values varying between 12 to 0.6 kΩ.cm-1.
|
|
