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(a) FT-IR and (b) XRD spectra of polyvinylidene difluoride (PVDF), BaTiO3, and PVDFBaTiO3 nanocomposite, (c) DSC thermogram of the nanocomposite with 20% BaTiO3 content.
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Polyvinylidene difluoride (PVDF) and its copolymers are promising electroactive polymers showing outstanding ferroelectric, piezoelectric, and pyroelectric properties in comparison with other organic materials. They have shown promise for applications in flexible sensors, energy-harvesting transducers, electronic skins, and flexible memories due to...
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... order to confirm the chemical structure of the printed films, FT-IR and XRD spectroscopy were employed. Figure 2a demonstrates the FT-IR spectra of PVDF, BaTiO3, and their printed nanocomposite. In PVDF, the absorption peaked at 1231, 1266, and 1401 cm −1 , which was attributed to the wagging vibration of CH2; the peak at 836 cm −1 originated from C-C-C asymmetric stretching, and absorption bands at 874 cm −1 were attributed to C-F vibrations [22][23][24]. ...
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... was characterized by two main absorption peaks, one at around 492 cm −1 , which was attributed to Ti-O vibrations, and the other at 1440 cm −1, related to BaTi-O stretching vibrations [29]. As seen in Figure 2a, the FT-IR spectrum of PVDF-BaTiO3 nanocomposite possessed all the characteristic peaks of both materials. Although the characteristic peaks of PVDF and BaTiO3 overlapped at 490 and 1440 cm −1 , the broad absorption bands of BaTiO3 were distinguishable within the sharp peaks of PVDF. ...
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... order to confirm the chemical structure of the printed films, FT-IR and XRD spectroscopy were employed. Figure 2a demonstrates the FT-IR spectra of PVDF, BaTiO 3 , and their printed nanocomposite. In PVDF, the absorption peaked at 1231, 1266, and 1401 cm −1 , which was attributed to the wagging vibration of CH 2 ; the peak at 836 cm −1 originated from C-C-C asymmetric stretching, and absorption bands at 874 cm −1 were attributed to C-F vibrations [22][23][24]. ...
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... 3 was characterized by two main absorption peaks, one at around 492 cm −1 , which was attributed to Ti-O vibrations, and the other at 1440 cm −1, related to Ba-Ti-O stretching vibrations [29]. As seen in Figure 2a, the FT-IR spectrum of PVDF-BaTiO 3 nanocomposite possessed all the characteristic peaks of both materials. Although the characteristic peaks of PVDF and BaTiO 3 overlapped at 490 and 1440 cm −1 , the broad absorption bands of BaTiO 3 were distinguishable within the sharp peaks of PVDF. ...
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... the characteristic peaks of PVDF and BaTiO 3 overlapped at 490 and 1440 cm −1 , the broad absorption bands of BaTiO 3 were distinguishable within the sharp peaks of PVDF. To further confirm the chemical structure of the printed films, XRD measurements were carried out on a pure PVDF film, BaTiO 3 , and the nanocomposite (Figure 2b). PVDF showed a broad XRD peak starting at 2θ = 15.5 • and finishing at 2θ = 21.7 • . ...
Citations
... However, the ferroelectric, piezoelectric, and thermoelectric properties of the polymer are solely derived from the polar phases of β and γ. Agarwala et al. [43] reported an approach to ...
Miniaturization and flexibility are becoming the trend in the development of electronic products. These key features are driving new methods in the manufacturing of such products. Printed electronics technology is a novel additive manufacturing technique that uses active inks to print onto a diverse set of substrates, realizing large-area, low-cost, flexible and green manufacturing of electronic products. These advantageous properties make it extremely compatible with flexible electronics fabrication and extend as far as offering revolutionary methods in the production of flexible electronic devices. In this paper, the details of a printing process system are introduced, including the materials that can be employed as inks, common substrates, and the most recently reported printing strategies. An assessment on future setbacks and developments of printed flexible electronics is also presented.
... This is good since it shows that the shapes of the peaks and symmetry are maintained, which further assures that there are no changes in the chemical states of barium, hence the stability and integrity of the BaTiO 3 phase in the nanocomposite. 30 Figure 2e shows the core-level XPS spectra for the Ti 2p area, showing the spin−orbit doublet peaks Ti 2p 3/2 and Ti 2p 1/2 for the samples, S1 sample and S3 nanocomposite. The pure BaTiO 3 spectrum shows a 2p 3/2 peak at 458.1 eV and a Ti 2p 1/2 peak at 463.4 eV, with a spin−orbit splitting of 5.3 eV. ...
... As printed electronics (PEs) continue to advance, there is a need for design methods to direct innovations for achieving further multifunctional structures using electroactive polymer (EAP) [30][31][32][33][34][35][36][37]. Unfortunately, recent research suggests that the PE technologies remain underutilized in a large industrial scale [38][39][40] because of unpracticable and complex processes. ...
To treat cardiovascular diseases (i.e., a major cause of mortality after cancers), endovascular-technique-based guidewire has been employed for intra-arterial navigation. To date, most commercially available guidewires (e.g., Terumo, Abbott, Cordis, etc.) are non-steerable, which is poorly suited to the human arterial system with numerous bifurcations and angulations. To reach a target artery, surgeons frequently opt for several tools (guidewires with different size integrated into angulated catheters) that might provoke arterial complications such as perforation or dissection. Steerable guidewires would, therefore, be of high interest to reduce surgical morbidity and mortality for patients as well as to simplify procedure for surgeons, thereby saving time and health costs. Regarding these reasons, our research involves the development of a smart steerable guidewire using electroactive polymer (EAP) capable of bending when subjected to an input voltage. The actuation performance of the developed device is assessed through the curvature behavior (i.e., the displacement and the angle of the bending) of a cantilever beam structure, consisting of single- or multi-stack EAP printed on a substrate. Compared to the single-stack architecture, the multi-stack gives rise to a significant increase in curvature, even when subjected to a moderate control voltage. As suggested by the design framework, the intrinsic physical properties (dielectric, electrical, and mechanical) of the EAP layer, together with the nature and thickness of all materials (EAP and substrate), do have strong effect on the bending response of the device. The analyses propose a comprehensive guideline to optimize the actuator performance based on an adequate selection of the relevant materials and geometric parameters. An analytical model together with a finite element model (FEM) are investigated to validate the experimental tests. Finally, the design guideline leads to an innovative structure (composed of a 10-stack active layer screen-printed on a thin substrate) capable of generating a large range of bending angle (up to 190°) under an acceptable input level of 550 V, which perfectly matches the standard of medical tools used for cardiovascular surgery.
... Vibration Absorption bands for PVDF crystal phase in FTIR[21,36]. ...
Piezoelectric composite fibers have various applications such as energy harvesting and human body monitor devices. Therefore, the construction of fibers that have the highest piezoelectric efficiency while using materials with the least toxicity is of great importance for health. Consequently, in the research a head PZT/PVDF (Lead Zirconate Titanate/Polyvinylidene fluoride) and
Lead free BaTiO3/PVDF (Barium Titanate/Polyvinylidene fluoride) 0–3 connection type composites nanofibers were fabricated by Electrospinning method. Dielectric constant with Impedance analyzer, sensitivity with handmade device and their crystalline properties by using FTIR and XRD, were compared. The results showed, adding BaTiO3 will increase the percentage of β-Phase crystal formation more than adding PZT which subsequently leads to a higher dielectric constant.
... The addition of BaTiO 3 to PVDF not only induces β-phase crystallinity but also improves the overall crystallinity of the composite. This is because BaTiO 3 particles provide a substrate for the growth of PVDF crystals, leading to a more ordered crystalline structure [36]. ...
This work aims to enhance the piezoelectric response of PVDF films through the incorporating of BaTiO3 nanoparticles as well as corona poling and cold plasma treatments. An optimized wet ball-milling process was used to fabricate BaTiO3 nanoparticles using commercial submicron BaTiO3 particles. In addition, a fluoroalkyl silane (FAS) solution was used to functionalize the surface of BaTiO3 nanoparticles to prevent the agglomeration of the nanoparticles and induce more affinity with the PVDF matrix. The morphology of PVDF-BaTiO3 composite films was characterized using scanning electron microscopy (SEM). Fourier transforms infrared (FTIR) spectroscopy and X-ray diffractometry (XRD) were used to investigate the phase analysis of samples. The results revealed that incorporating the functionalized BaTiO3 nanoparticles within the PVDF layer increases the piezoelectric response of pure PVDF from 1.05 mV to 1.46 mV which is more than that of the sample with incorporated micron size BaTiO3 (1.28 mV). Cold plasma treatment increased the wettability of PVDF, significantly, which reduced the water contact angle from 71° to 21°. In addition, the corona polarization enhanced the piezoelectric response of the samples, which increased the output voltage to 1.53 mV.
... Because increasing the amount of ceramic that is added to PVDF causes the surface of the fiber to become rougher or causes aggregation, as identified in articles [7][8]11 , other techniques, such as using doubled layers of nanofibers, were utilized instead. This indicates that the mechanism of interference between the two layers of the fibrin structure is distinct, and it is also ideal for converting the separate phases to the -phase responsible for the piezoelectric activity in this study [6][7][8]12 . This means that the process of interference between the fibrin structure's double layers is done distinctively, as well as this is perfect for converting the different phases to the β-phase responsible for the piezoelectric property in this work. ...
... ): Representation of improving the β-phase structure of nanoparticles BT into PVDF12 ...
This study enhances the piezoelectric effects of electrospun nanocomposite nanofibersformed from layers of PVDF-Ceramic nanogenerator. Through the use of several sidenanocomposites, the nanogenerator has evolved from a single to a double layer. Theoutputting piezoelectric is very highly dependent on fabricated performance. Aresearcher has previously demonstrated interest in mixed nanocomposites (PZB) thatare capable of enhancing performance and boosting output voltage to 7,200 V byapplying 0.2657 N of force and 2.5 Hz of frequency. Thus, fabricate thin generatorcompanion of nanocomposite materials fibers together with concentrations (16%PVDF–18%ZnO) and (12%PVDF–20%BaTiO3). The phase transition of this generator is detailedusing XRD, SEM, and FTIR, and its electrical response characteristics are assessed usingan oscilloscope.
... The polar phase is exhibited by β-crystallinity [6,47,48]. In its all-trans conformation, PVDF exhibits high ferroelectric and piezoelectric properties, aided by the greater presence of the β-crystalline phase [49][50][51][52]. Researchers reported that PVDF pellets have 49.4% β-phase [52]. ...
A flexible and portable triboelectric nanogenerator (TENG) based on electrospun polyvinylidene fluoride (PVDF) doped with copper oxide (CuO) nanoparticles (NPs, 2, 4, 6, 8, and 10 wt.-% w.r.t. PVDF content) was fabricated. The structural and crystalline properties of the as-prepared PVDF-CuO composite membranes were characterized using SEM, FTIR, and XRD. To fabricate the TENG device, the PVDF-CuO was considered a tribo-negative film and the polyurethane (PU) a counter-positive film. The output voltage of the TENG was analyzed using a custom-made dynamic pressure setup, under a constant load of 1.0 kgf and 1.0 Hz frequency. The neat PVDF/PU showed only 1.7 V, which further increased up to 7.5 V when increasing the CuO contents from 2 to 8 wt.-%. A decrease in output voltage to 3.9 V was observed for 10 wt.-% CuO. Based on the above results, further measurements were carried out using the optimal sample (8 wt.-% CuO). Its output voltage performance was evaluated as a function of varying load (1 to 3 kgf) and frequency (0.1 to 1.0 Hz) conditions. Finally, the optimized device was demonstrated in real-time wearable sensor applications, such as human motion and health-monitoring applications (respiration and heart rate).
... The absorption bands at 3020 cm -1 and 2980 cm -1 corresponded to the -CH2 asymmetric and symmetric vibration of PVDF [27]. The bands located at 1266 cm -1 and 1400 cm -1 were attributed to -CH2 wagging vibration [27,28]. The absorption band at 840 cm -1 shows -CF2 stretching [29]. ...
Graphical abstract 1 Research Paper Hydrophilic additives Microfiltration membrane Non-solvent-induced phase separation PVDF PEG • Membranes were fabricated by the non-solvent induced phase separation (NIPS) method. • The SEM images showed thick skin on the upper and macro-voids in the lower layer. • The expected performance could not be reached because the PEG leaked from the membrane.
... Recent years have shown growing research interest in using DODpiezoelectric printhead as a tool for various advanced applications. It has been used to deposit versatile functional materials such as biological molecules, [16,[50][51][52][53] conductive inks [54][55][56][57] and hydrogels. [58][59][60] ...
... Lysozyme, however, can be adsorbed on plasma treated PET by multilayers, [171] where the first layer is governed by electrostatic forces [168] and the second layer by weaker protein-protein interactions. [160] XPS results ( Figure 19) with higher N% for plasma treated surface supported 54 such formation of multilayers. Thus, it promoted higher and stronger lysozyme adsorption and can be suitable for bio-sensing applications. ...
This thesis explores the possibilities of printing enzymes using resource-efficient technologies to promote the binding of other proteins and biomaterials on synthetic textiles. This strategy can be used to develop advanced textiles for applications, for example, in antimicrobial, drug delivery and biosensing. Digital inkjet printing was combined with enzyme technology to ensure minimum use of water, chemicals and energy in textile manufacturing processes.
Inks containing two enzymes, lysozyme and tyrosinase, were formulated by adjusting several rheological and ionic properties. The activity of these enzymes was optimised while being printed through two different industrial grade piezoelectric printheads. The theoretical printability of the prepared inks was calculated. The effect of printhead temperature and number of printing passes on the activity was evaluated. Polyester (polyethylene terephthalate) and polyamide-6,6 were pre-treated through several techniques to understand their effect on enzyme adhesion, binding and activity retention. Tyrosinase was used to bind lysozyme on plasma activated polyamide-6,6 surface. The effects of printing these two enzymes in various sequences, i.e. tyrosinase before lysozyme and vice-versa on binding stability and activity, were studied. Influence of the printing process on enzyme kinetics was evaluated. Ability to store and reuse printed fabrics was also studied.
Lysozyme and tyrosinase containing inks showed activity retention of 85% and 60%, respectively. Activity of lysozyme containing ink was optimum at 10–15 mPa.s when glycerol was used as a viscosity modifier. However, the optimum viscosity for tyrosinase containing ink was at 6–9 mPa.s, and carboxymethyl cellulose was found to be the most favourable modifier. For both inks, a surfactant amount below the critical micelle concentration was considered to be the most effective for printing. Among the studied fabric pre-treatment methods (alkaline, cutinase and plasma), it was found that the activity and stability of the enzyme were dependent on the nature of the pretreatment processes, which can be beneficial for different application areas, e.g. drug release and bio-sensing. Upon printing both inks on a plasma treated polyamide-6,6, tyrosinase was able to catalyse lysozyme protein to bind it on fabric. A maximum of 68% lytic activity was retained by lysozyme when it was printed after tyrosinase. This fabric showed inhibition of bacterial growth and retained almost half of its initial activity when cold stored for a month.
... There is evidence that the β phase may be obtained and improved by introducing various nucleating fillers like barium titanate [17], zinc oxide [18], carbon nanotubes [19], nanowires [20], silver nanoparticles [21], and so on. Besides this, modeling clay must be annealed at room temperature to reach the β phase, which is a facile and feasible approach to acquiring piezoelectricity [13,22]. Furthermore, Singh et al. [23] integrating ZnO-PVDF film with PTFE, and were able to fabricate a piezo-tribo-based hybrid synergetic nanogenerator. ...
... This is a sign that the material undergoes the process of changing phases from the wet state to the dry state during annealing, which expands the β phase of the dry modeling clay. Furthermore, the peak of dry modeling clay is sharper than that of wet modeling clay, which is an indication that the dry modeling clay is β phase greatly influenced by the annealing process [22,40]. ...
The next generation of power sources for wearable electronics is anticipated to be nanogenerators based on triboelectric and piezoelectric mechanisms, which have proven to be effective at converting biomechanical energy into electrical energy. In this work, the piezoelectric and triboelectric effects of modeling clay were deeply explored. It is interestingly found that dry modeling clay possesses increasing β phase crystallinity when wet modeling clay undergoes annealing treatment. Based on the piezoelectric mechanism, the single-layer device of dry modeling clay delivers a power density of 1 W/m 2 , 250 times higher than the single-layer device of wet modeling clay. By piezoelectric mechanism, the single-layer device of polystyrene (PS) film delivers a power density of 0.35 W/m 2. It is amazing that the nanogenerator composed of dry modeling clay and PS double layers achieves a high-power density of 3.75 W/m 2. Through deep investigation, it is found that a synergetic piezo-triboelectric mechanism takes effect. The piezoelectric effects in each dry modeling clay, the porous structure of the polystyrene film, and the triboelectric effects occurring between the two layers are all involved. It was demonstrated that 200 and 300 commercial LED lights could be powered by the dry modeling clay-based device and the dry J o u r n a l P r e-p r o o f modeling clay-PS double layer device, respectively, showing that the devices have the potential to be used for energy harvesting.
