Browsing by Subject "Thermal drawing"

Now showing 1 - 4 of 4

Open Access
Graphene nanoplatelet integrated thermally drawn PVDF triboelectric nanocomposite fibers for extreme environmental conditions
(Wiley-VCH Verlag GmbH & Co. KGaA, 2024-01-03) Sadeque, Md Sazid Bin; Rahman, Mahmudur; Hasan, Md Mehdi; Ordu, Mustafa
Triboelectric nanogenerators (TENGs) utilize the synergetic eﬀect of triboelectriﬁcation and electrostatic induction to guide electrons through an external circuit, enabling low-frequency mechanical and biomechanical energy harvesting and self-powered sensing. Integrating 2D material with a high speciﬁc surface area into ﬂexible ferroelectric polymers such as polyvinylidene diﬂuoride (PVDF) has proven to be an eﬃcient strategy to improve the performance of TENG devices. Scalable fabrication of graphene-integrated PVDF nanocomposite ﬁber using thermal drawing process is demonstrated for the ﬁrst time in this study. The open-circuit voltage and short-circuit current show 1.41 times and 1.48 times improvement with the integration of 5% graphene in the PVDF ﬁbers, respectively. The TENG fabric shows a maximum power output of 32.14 μW at a matching load of 7 M𝛀 and a power density of 53.57 mW m$^{−2}$. The ﬁbers exhibit excellent stability in harsh environmental conditions such as alkaline medium, high/low temperature, multi-washing cycle, and long-time usage.
Open Access
Scalable fabrication of MXene-PVDF nanocomposite triboelectric fibers via thermal drawing
(Wiley, 2022-12) Hasan, Md Mehdi; Sadeque, Md Sazid Bin; Albasar, Ilgın; Pecenek, H.; Dokan, F. K.; Onses, M. Serdar; Ordu, Mustafa
In the data-driven world, textile is a valuable resource for improving the quality of life through continuous monitoring of daily activities and physiological signals of humans. Triboelectric nanogenerators (TENG) are an attractive option for self-powered sensor development by coupling energy harvesting and sensing ability. In this study, to the best of the knowledge, scalable fabrication of Ti3C2Tx MXene-embedded polyvinylidene fluoride (PVDF) nanocomposite fiber using a thermal drawing process is presented for the first time. The output open circuit voltage and short circuit current show 53% and 58% improvement, respectively, compared to pristine PVDF fiber. The synergistic interaction between the surface termination groups of MXene and polar PVDF polymer enhances the performance of the fiber. The flexibility of the fiber enables the weaving of fabric TENG devices for large-area applications. The fabric TENG (3 × 2 cm2) demonstrates a power density of 40.8 mW m−2 at the matching load of 8 MΩ by maintaining a stable performance over 12 000 cycles. Moreover, the fabric TENG has shown the capability of energy harvesting by operating a digital clock and a calculator. A distributed self-powered sensor for human activities and walking pattern monitoring are demonstrated with the fabric. © 2022 Wiley-VCH GmbH.
Open Access
Thermal drawing of low-dimensional material-integrated triboelectric fibers for healthcare applications
(2024-07) Sadeque, Md Sazid Bin
The potential of flexible wearable devices and sensors to revolutionize healthcare lies in their ability to facilitate real-time monitoring. However, many of these wearable sensors are extensive energy consumers, and the requirement of bulky energy storage devices significantly hampers their acceptability. Currently available sensing devices mostly employ film-based devices, which lack breathability, reducing their applicability in widespread healthcare applications. Triboelectric nanogenerators (TENGs) are environmentally sustainable devices that convert mechanical and biomechanical energy into electrical output through the synergetic processes of triboelectrification and electrostatic induction. These devices effectively harvest low-frequency mechanical and biomechanical energy and enable self-powered sensing. TENG performance can be enhanced by incorporating low dimensional materials with high specific surface area into flexible ferroelectric polymers. Ferroelectric polyvinylidene fluoride (PVDF) and its copolymers are particularly advantageous due to their high dielectric constant and abundant highly electronegative fluorine ions. Various low dimensional materials can interact with the polar groups of PVDF and reorient them to conform to electroactive phases. Moreover, they can also form micro-capacitors and modulate the surface properties of nanocomposite. In this thesis, we aim to prepare a triboelectric nanogenerator integrated textile fiber with self-energy generating ability and breathability as textiles. We employed the thermal drawing process as a fabrication platform for preparing continuous triboelectric fibers. Graphene nanoplatelet (GNP) and Molybdenum disulfide (MoS2) are added to the PVDF matrix to improve triboelectric properties. β phases of thermally drawn nanocomposite fibers demonstrate significant improvement and were increased to 37.6%, 39.5%, and 43.3% for 1, 3, 5% GNP integration. For the case of MoS2, β phase increases to 47.5% for 3 wt%MoS2; however, β phase decreases beyond 3 wt%. The nanocomposite TENG fibers demonstrate improved triboelectric properties. The fibers show superior sensitivity, flexibility and durability, enabling their applications in critical healthcare applications.
Open Access
Thermal drawing of MoS₂ integrated PVDF triboelectric fiber for continuous respiration monitoring
(Wiley-VCH Verlag GmbH & Co. KGaA, 2024-12-19) Sadeque, Md Sazid Bin; Rahman, Mahmudur; Hasan, Md Mehdi; Ordu, Mustafa
Triboelectric nanogenerators (TENGs) are environmentally sustainable energy harvesting devices that can convert mechanical and biomechanical energy into electrical output through the synergistic process of triboelectrification and electrostatic induction. Incorporating polyvinylidene fluoride (PVDF) and its copolymers into flexible TENG is particularly advantageous because of the abundance of highly electronegative fluorine ions and high dielectric constant. MoS₂ can interact with PVDF dipoles to improve PVDF's β phase content, thereby improving the triboelectric property of the polymer nanocomposite fibers. In this study, thermally drawn PVDF TENG fibers are fabricated, incorporating various concentrations of $MoS_2$ for the first time. The enhanced β phase property in the nanocomposite fiber improves the triboelectric output where 3 wt.% $MoS_{2-}$ PVDF fiber demonstrates a maximum peak power output of 17.64 µW, exhibiting a threefold increment compared to 0 wt.% $MoS_{2-}$ PVDF fiber. Simultaneous integration of multiple nanomaterials ($MoS_2$ and graphene) is also investigated to analyze the triboelectric fiber's β phase formation and electrical performance. Harnessing the superior sensitivity of the $MoS_2$ integrated triboelectric fiber, a self-powered wearable mask is designed for continuous human respiration monitoring.