Development of MXene-Enhanced Polyvinyl Alcohol Nanofibers: A Comprehensive Study on Synthesis and Characterization

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This study focuses on synthesizing polyvinyl alcohol (PVA) and Ti 3 C 2 T x MXene into a nonwoven nanofiber (NF) composite mat using an electrospinning. Following the electrospinning process, the fibers underwent pyrolysis, a crucial step that enhances their electrical conductivity and structural integrity. To characterize the nanofibers, an X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (SEM) were performed. XRD and FTIR analysis confirmed the presence of both PVA and MXene, while SEM revealed improved morphological properties, including increased surface area and a higher number of active sites. The Raman spectra provided insights into defect densities, with the I D /I G ratio indicating that the incorporation of MXene and subsequent pyrolysis effectively increased defect density in PVA while enhancing its amorphous nature. Importantly, electrical conductivity measurements demonstrated a substantial enhancement in direct current conductivity for the pyrolyzed PVA-MXene composite fibers. The improved defect densities created an additional pathway for charge carriers through localized stress distribution, leading to higher conductivity. polymer-MXene composite nanofibers pyrolysis electrical conductivity Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Figure 8 1. Introduction MXenes, a remarkable class of two-dimensional (2D) transition metal carbides or nitrides, have gained significant interest in recent years due to their unique properties. These metal layered 2D materials are synthesized through selective etching from their parent MAX phase. The reduction dimensions in MXenes exhibit significantly enhances properties not found in their bulk counterparts, making them suitable for a wide range of applications, including electronics, optoelectronics, and catalysis [ 1 ]. However, similar to other 2D materials, MXenes tend to stack and aggregate “face-to-face” due to strong van der Waals forces, which can severely hinder their performance in practical applications [ 2 ]. To address this issue, various methods have been developed to prevent restacking. One common approach involves creating composites with polymers, which weakens the interplanar attraction and increases interlayer separation. Polymers when combined with MXenes, can enhance mechanical and thermal properties while preserving excellent hydrophilicity and metallic conductivity, making then ideal materials for wearable electronic devices and batteries [ 3 ]. A variety of polymers including PAN [ 4 ], PVDF [ 5 ], PVA [ 6 ], PEO [ 7 ], PMMA [ 8 ], PS [ 9 ] etc. have been utilize to make polymer MXene composites tailored for specific applications [ 10 ]. Polyvinyl alcohol (PVA), known for its strong hydrophilicity, suggests that MXenes exhibit good compatibility with PVA. Electrospinning is a widely used technique for producing nanofibers with high surface area and porosity, which are essential for enhancing the performance of composite materials. Various studies have reported on the electrospinning of different polymers [ 11 ]. For instance, Cheng.et.al. [ 12 ] found that incorporating an MXene/AgNP composite into a PVDF solution significantly increased electrical conductivity from 40 to 1,148 µS/cm. This enhancement also improved the piezoelectric properties of PVDF fibers, enabling the development of self-powered, wearable electronic devices. Similarly, Tan et.al [ 13 ] reported that PMMA/MXene nanocomposites exhibited electrical conductivity over 3000 times higher than pure PMMA (1 × 10 − 14 to 1 × 10 − 13 S m − 1 ). Additionally, Patrik.et.al [ 14 ] noted that PVA nanofibers containing 0.14 wt.% Ti 3 C 2 T x demonstrated a DC conductivity of 0.8 mS cm -1 superior to that of similar composites prepared using other methods. Yunyun.et.al [ 15 ] reported that adding MXene to polymer at very low concentration (0.0001 wt %- 0.002 wt %) suppressed space charge within polymeric units. This reduced filler concentration improved compatibility and dispersion at the interface while minimizing negative impacts on PVA’s physical performance. Sutasinpromprae et al. [ 16 ] identified that internal and surface flaws introduced during heat treatment govern the tensile strength of fibers. They synthesized carbon fibres from PAN through electrospinning followed by pyrolysis. At controlled high-temperatures, the non-conductive polymer undergoes thermal decomposition to form a carbonized structure that facilitates charge carrier transfer across the film. Moreover, pyrolysis also improves thermal stability and chemical resistance. [ 17 ][ 18 ][ 19 ]. In the present study, we explore the synthesis of PVA-MXene based fibers through electrospinning followed by pyrolysis. We aim to investigate the structural, morphological, and electrical properties of these fibers to assess their suitability for various applications. 2. Materials and Methods 2.1 Preparation of Ti 3 C 2 MXene Ti 3 AlC 2 (Aritech Chemazone Pvt. Ltd.) was employed to synthesize Ti 3 C 2 nanoflakes (NFs) through exfoliation, adhering to the procedure outlined by Lipatov et.al. [ 20 ]. Initially, 1 g of LiF was dissolved in 20 mL of 6 M HCl solution, and then 1 g of Ti 3 AlC 2 was gradually introduced over a 10 min period to minimize initial overheating resulting from the exothermic reaction. Subsequently, the temperature was raised to 35°C, and the reaction was maintained with continuous stirring at 550 rpm for 48 hours. After repeated washing with deionized water, the pH of the resulting MXene powder was neutral. The product was collected via vacuum-assisted filtration with a PVDF membrane and subsequently dried in a vacuum desiccator at room temperature for 24 hours. To achieve further delaminate, the Ti 3 AlC 2 solution was centrifuged at 3500 rpm for 1 h, discarding the supernatant. A colloidal solution of MXene was collected from the bottom of the vial. The resulting Ti 3 C 2 NFs were characterized by X-ray diffractometer (XRD) (PANalatical Xpert3 Powder) and a field emission scanning electron microscope (FE-SEM) (Hitachi SU-6600). 2.2 Preparation of PVA fiber Polyvinyl alcohol (PVA) (Thermo Fisher Scientific India Pvt. Ltd, MW 125 g/mol, degree of hydrolysis 85–89%) was utilized as the primary material for the synthesis of nanofibers. The PVA solution was prepared by gradually adding 5 g of PVA powder to 50 ml of deionized water to prevent lump formation. The mixture was continuously agitated for 3 hours, during which the temperature was gradually increased to 90°C while maintaining a stirring speed of 1500 rpm. The prepared solution was carefully transferred into a 12 ml syringe, ensuring the absence of air bubbles. The syringe was then positioned into the electrospinning apparatus, specifically the Holmarc-model HO-NFES-043. A voltage of 15 kV was applied between the needle and the mandrel, with the needle serving as the positive terminal and the mandrel as the negative terminal. The flow rate was adjusted to 0.2 ml per hour, and the distance between the needle and the mandrel was maintained at 12 cm. Electrospinning was conducted for a duration of 6 hours to obtain a coherent nanofiber mat on the mandrel. Following electrospinning, the developed fibers were carefully peeled from the mandrel and subjected to hydrolysis by heating at 155°C for 6 hours, resulting in partial dehydration [ 21 ]. The hydrolysed sample was subsequently subjected to pyrolysis in a tubular furnace at 800°C with a heating rate of 10°C/min. The samples were maintained at this temperature for 90 minutes in an argon atmosphere. The sample that underwent hydrolysis was designated as PVA-dried, whereas the sample subjected to pyrolysis was labelled as PVA pyro. 2.3 Preparation of PVA-MXene nanofibers 80 mg of MXene NFs were added to 50 ml of the PVA solution prepared as described in section 2.2 , resulting in a 0.016 wt % MXene solution. The PVA-MXene solution was then subjected to magnetic stirring at a rotational speed of 1500 rpm for 24 hours to ensure uniformity and consistent mixing. After stirring, the solution was carefully transferred into a 12 ml syringe, taking care to avoid the formation of air bubbles. Electrospinning was conducted using the same parameters outlined in section 2.2 . Once the electrospinning process was complete, the fibers were peeled from the mandrel and underwent multiple stages of heat treatment, as described in Section 2.2 . The samples that underwent hydrolysis was designated as PVA-MXene-dried, while the sample that underwent pyrolysis was labelled PVA-MXene-pyro. 2.4 Test Characterization The morphological characteristics of the as-spun and heat-treated samples, referred to as HT samples, were characterized using field emission scanning electron microscopy (FE-SEM). XRD analysis was conducted over the range of 2θ = 5° to 60° with a step size of 0.15°. To identify the functional groups, present, Fourier transform infrared spectrometer (FTIR, PerkinElmer Frontier) was employed. Additionally, Raman spectroscopy (Horiba Lab Ram-HR Evolution confocal Raman spectrometer) measurements were taken using a diode-pumped solid-state laser with a wavelength of 532 nm, capturing absortion spectra in the range of 200–1200 cm –1 . Conductivity measurements of the electrospun PVA and PVA-MXene samples were performed on a carbon fiber mat to ensure a continuous conductive path for accurate conductivity assessment. The pyrolyzed samples coated on the carbon fiber mat were designated as pyrolyzed CF, pyrolyzed CF-PVA and pyrolyzed CF-PVA-MXene. An LCR meter (HIOKI IM-3536) was utilized for these measurements, employing four probes with frequencies ranging from 1 kHz to 1 MHz. The samples for conductivity measurement were specifically prepared by electrospinning PVA and PVA-MXene onto the carbon fiber mat, facilitating a continuous conductive path for the conductivity evaluation. 3. Results and Discussions 3.1 Characterization of MXenes The X-ray diffraction patterns of the Ti 3 AlC 2 MAX phase, exfoliated Ti 3 C 2 MXene, and delaminated Ti 3 C 2 MXene NFs are shown in Fig. 1 . The as-purchased MAX phase predominantly consisted of the Ti 3 AlC 2 phase. Following etching with LiF and HCl, it was evident that all peaks in the MXene data, except for the (002) and (104) peaks, nearly vanished. Notably, the (002) peak exhibited a downward shift in angle from 9.5° to 6.5°, indicating the selective etching of aluminium from the MAX phase. Additionally, the full width at half maximum (FWHM) of the (002) peak increased from 0.23 to 0.63 during the etching process. After delamination, the (104) peak diminished, further confirming the two-dimensional nature of the obtained Ti 3 C 2 MXene NFs [ 20 ]. The d-spacing after delamination was measured to be 14.39 A˚. Figure 2 presents SEM images illustrating the morphological characteristics of the Ti 3 AlC 2 MAX phase and Ti 3 C 2 MXene. The delamination of the Ti 3 C 2 MXene is specifically highlighted in Fig. 2 (b). The analysis revealed the presence of a characteristic accordion-like shape and cross-sectional shear slip in the multilayer MXenes, providing compelling evidence for the successful delamination of Ti 3 C 2 [ 22 ]. 3.2 Characterisation of PVA-nanofibers The electrospinning process for producing defect-free fibers is influenced significantly by the molecular weight and concentration of the polymer solution. To achieve smooth, bead-free fibers, it is essential to use the polymer solution with a concentration of atleast 10 wt.% polyvinyl alcohol (PVA) [ 23 ]. At this optimized PVA concentration, the solution forms a stretchable network of PVA chains, which helps prevent network rupture during the electrospinning process. The morphology and distribution of the fiber diameter for each obtained mat are illustrated in Fig. 3 (b) and (c). Figure 3 (a) represents the XRD patterns for PVA powder, PVA nanofiber, and pyrolyzed PVA nanofibers. The XRD pattern of pure PVA powder shows peaks at 2θ = 20° and 2θ = 40.5°, corresponding to the \(\:\stackrel{-}{(1}00)\) and \(\:\stackrel{-}{(1}11)\) crystallographic planes of PVA, respectively. These peaks indicate the semi-crystalline nature in pure PVA and suggest polymer chain alignment due to hydrogen bonding [ 24 ]. However, after the electrospinning process, these peaks vanished, leaving only a single broad peak around 2θ = 20°, suggesting a transition to a predominantly amorphous structure with significantly reduced crystallinity. Despite being a semi-crystalline polymer, the rapid solidification of the polymer fluid during the electrospinning process is the cause of the lack of crystallinity in the as-spun fibers [ 25 ]. A broad peak around 2θ = 24° in PVA-fiber-pyrolyzed, corresponding to the (002) crystallographic plane, suggests significant structural transformations. This peak likely arises from weak intermolecular interaction of the -OH groups in the PVA, which leads to the disruption of its original linear ordered structure and facilitates a transformation into a ladder-like polymeric structure. Such changes indicate the formation of extremely tiny and randomly organized pseudo-graphite layers, consistent with disordered micrographite stacking [ 26 ]. At the optimum PVA concentration, the polymer solution formed a flexible network of interconnected PVA chains, effectively preventing fiber rupture during electrospinning. Figure 3 (b) presents the SEM micrographs and the corresponding fiber distribution for the PVA electrospun mat. This shows that the randomly aligned fibers were characterized by a size distribution spanning from 40 to 280 nm. The average diameter of these fibers, determined through image-J analysis, was found to be 235 nm. During hydrolysis, an increase in temperature led to partial melting of the fibers, resulting in structural changes such as fiber merging, fusion, and alterations in surface texture. These changes induced dynamic crystallization and recrystallization in the melted zones, as illustrated in Fig. 3 (c). The pyrolyzed fibers displayed in the Fig. 3 (c) also exhibited random orientation and a broad size distribution, ranging from 25 to 275 nm. The primary chemical composition of PVA is represented by the repeating unit – (CH 2 –CHOH) n with the individual building block being (CH 2 = CHOH). The FTIR spectrum analysis presented in Fig. 4 (a) highlight the prominent peaks related to PVA. Notably, peaks located around 2000 cm –1 in all three spectra are attributed to C-H bond bending. The spectral characteristics of the electrospun PVA fibers closely resemble those of the PVA powder, albeit with slight variations in relative intensity and peak position. The -OH stretching of electrospun PVA, observed at 3278 cm -1 , remains unchanged in its position as compared to PVA powder. However, it becomes broader in PVA dried due to the hydrolysis process, suggesting the elimination of water molecules [ 27 ]. Substantial fluctuations noted in the carbonyl stretching region between 1700 cm –1 to 1735 cm –1 for the PVA fiber compared to the PVA powder. A more profound dip at 1711 cm –1 is identified in the PVA dried, indicating the formation of carbonyl groups as a result of hydrolysis, which involves the elimination of water and subsequent chain reactions. Additionally, the asymmetric stretching band of -CH 2 at 2935 cm -1 develops a shoulder in the PVA dried compared to PVA powder and PVA fibers. The C = C stretching mode of PVA is associated with the band at 1143 cm -1 , which is crystalline sensitive [ 25 ]. A notanble reduction of this peak is observed in the PVA fiber when compared to PVA powder, indicating a transition from crystalline to amorphous structure. Furthermore, a greater dip in this peak for the PVA dried suggests the development of a ladder-like structure. The Raman spectra of the as-spun PVA fiber and pyrolyzed PVA fibers are presented in Fig. 4 (b). In the spectrum of the as-spun PVA, the most prominent scattering peaks corresponding to the stretching vibrations of -CH 2 and -CH groups, with a peak at 1440 cm -1 is attributed to the stretching vibrations of -CH and -OH within the PVA molecules. Following pyrolysis, two peaks appeared at 1334 cm -1 and 1585 cm -1 , corresponding to the D (characteristic of a disordered sp 3 phase) and G bands (characteristic of the in-plane stretching vibration mode E 2g of well-crystallized graphite) respectively. The defect density in carbon nanostructures is typically quantified by the intensity ratio between the D and G bands (I D /I G ). The (I D /I G ) ratio for pyrolyzed PVA is 1.904. This higher I D /I G suggests an increased level of disorder and defects within the material, which can be indicative of amorphous carbon. Figure 5 (a) displays the XRD patterns of the three samples: PVA powder, PVA-MXene fiber, and pyrolyzed PVA-MXene fiber. The electrospun PVA-MXene fiber exhibits a prominent amorphous peak at 2θ = 20°, indicating the absence of a crystalline phase and confirming its amorphous nature. After pyrolysis at 800°C, the peak at 2θ = 20° disappears, and a broad peak around 2θ = 24° emerges. The diffraction peak in the XRD pattern of the pyrolyzed PVA-MXene fiber is attributed to the (002) crystallographic plane of graphite. Figure 5 (b) presents the SEM image depicting the surface morphology and diameter of the fabricated nanofibers. Node-like lumps began to appear in the PVA-MXene fibers, indicating structural changes. The fibers exhibited a random orientation with a broad diameter distribution ranging from 140 nm to 300 nm. During the hydrolysis process at 195°C, further changes in fiber structure occurred, including merging and fusion among fibers, as well as alteration in surface texture. These modifications resulted in dynamic crystallization and recrystallization in the melted zone, as shown in Fig. 5 (c). Additionally, a random distribution of fibers was observed, with diameters ranging from 100 to 220 nm, and the average diameter was determined to be 198 nm. The FTIR spectra of PVA-MXene, PVA-MXene dried, and PVA were analyzed in the range of 400–5000 cm -1 , as shown in Fig. 6 (a). Common peaks at 2935 cm − 1 , 1143cm − 1 , 3278 cm − 1 , and 1090 cm − 1 , were observed in all three spectra [ 28 ][ 29 ]. The -OH stretching associated with hydrolysis is visible at 3278 cm -1 in the absorption peak of PVA MXene, resulting from intermolecular hydrogen bonding. Symmetric C-H bonding and -CH 2 bending are evident at 2935 cm − 1 and 1143 cm − 1 , respectively. Additionally, a peak corresponding to C–O stretching was observed in the PVA spectrum. Although MXene-influenced peaks are not prominently reflected in the graph, some shoulder peaks are noted between 300 cm -1 -500 cm -1 in the spectrum of PVA MXene pyrolyzed. These shoulders may arise from bond-breaking processes during hydrolysis. The presence of similar contours across the spectra confirms that physical interactions between PVA and Mxene were observed. Figure 6 (b) illustrates the Raman spectra of both pyrolyzed and as-spun PVA-MXene fibers. The most prominent scattering peak at 1440 cm -1 in the spectrum of as-spun PVA-MXene corresponds to the stretching vibrations of -CH and -OH groups in the PVA molecules. After pyrolysis, two new peaks appeared at 1334 and 1585 cm -1 , which are associated with the D and G bands, respectively [ 30 ]. The (I D /I G ) ratio for pyrolyzed PVA-MXene is measured at 1.293. This reduction in defect density, indicated by a decrease in the (I D /I G ) ratio, suggests that the pyrolyzed PVA-MXene possesses a more crystalline structure. In Fig. 7 (a), peak broadening and a decrease in intensity at 2θ = 20° are observed in the XRD patterns of both as-spun PVA and as-spun PVA-MXene fibers. This indicates an increase in the amorphous nature of the fibers upon the addition of MXene. In the FTIR spectra of the as-spun fibers, shown in Fig. 7 (b), only minor differences are noted when the MXene concentration is very low, specifically at 0.016 wt.%. Notably, an additional dip at 1087 cm -1 , corresponding to C = O stretching, is attributed to the presence of MXene [ 31 ]. Furthermore, a small but broad dip at 3278 cm -1 , associated with O-H stretching, is caused by inter- and intra-molecular hydrogen bonding. The Raman spectroscopic analysis of the as-spun PVA and PVA-MXene fibers, shown in Fig. 7 (c), reveals no significant differences in the corresponding characteristic peaks. However, several peaks, specifically the Eg and Ag modes associated with MXene, appear as shoulders below 700 cm -1 upon the addition of MXene. Figure 7 (d) presents the electrical conductivity results for the as-spun fibers of PVA and PVA-MXene spun on carbon fibers. The data indicate frequency independence in the lower frequency ranges, followed by a consistent and progressive increase in conductivity as frequency rises. This behaviour can be attributed to the presence of PVA, while the enhanced conductivity is primarily due to the incorporation of MXene. MXene facilitates a conductive pathway that integrates into the woven mat during the electrospinning process within the polymer matrix, further enhancing overall conductivity. In Fig. 8 (a), the XRD results for pyrolyzed PVA and PVA-MXene show very broad peaks, indicating their amorphous nature. The broadness observed in PVA-MXene is greater than that in PVA, which is attributed to its amorphous structure, making it potentially more suitable for battery applications. The FTIR spectral analysis of PVA dried PVA and PVA-MXene, depicted in Fig. 8 (b), shows similarities between peaks at 2935 cm − 1 , 3278 cm − 1 , and 1711 cm − 1 in both samples. However, there is a noticeable decrease in peak sharpness for PVA-MXene compared to the as-spun sample, suggesting structural degradation upon heating to 195 ˚C. In contrast, the appearance of these same peaks in dried PVA indicates an increase in crystallinity. Additionally, a small amount of shoulder formation is observed below 500 cm − 1 , which is attributed to MXenes. In the Raman spectroscopic analysis of pyrolyzed PVA and PVA-MXene, shown in Fig. 8 (c), the I D /I G ratios were found to be 1.294 and 1.904, respectively. This difference in the I D /I G ratio indicates a higher defect density and an increase in the amorphous nature of the PVA-MXene sample, which aligns with the findings from the XRD analysis. Figure 8 (d) compares the electrical conductivities of the pyrolyzed samples with those of pyrolyzed carbon fibers. The conductivity of the pyrolyzed CF-PVA sample was lower than that of the pyrolyzed CF sample. PVA, which is originally a dielectric material, undergoes degradation and structural changes during pyrolysis, potentially diminishing the continuous electrical pathways provided by carbon fibers. These insulating regions within the composite hinder electron transport. In contrast, the presence of MXene in pyrolyzed CF-PVA-MXene facilitated electron transport by creating conductive pathways in the voids left by the PVA. As a result, a significant improvement in conductivity was observed [ 14 ]. 4. Conclusion PVA-MXene based fibers were successfully synthesized through an electrospinning process and subsequently pyrolyzed to enhance conductivity. X-Ray diffraction analysis revealed the amorphous nature of both the as-spun PVA and PVA-MXene samples, indicated by the presence of broader peaks that signify a lack of long-range order in their structure. The increasing broadness and shoulder formation in the peak at 2θ = 24° for the pyrolyzed PVA-MXene sample further confirmed its suitability for battery applications. The SEM results provided insight into the morphological properties of the electrospun fibers, which exhibited increased surface area and, consequently, a higher number of active sites. The average diameter of the PVA fibers was measured at 235 nm, however, upon the addition of MXene, this diameter decreased to 198 nm, facilitating improved transport properties. FTIR analysis confirmed the presence of MXenes encapsulated within the polymer matrix of the PVA fiber mat. The elimination of certain peaks during heat treatment indicated structural deformations leading to carbonization. The I D /I G ratios obtained from Raman spectroscopy suggested that the presence of MXenes improved defect density in PVA while enhancing its amorphous characteristics. Additionally, electrical conductivity results demonstrated a significant impact from the incorporation of MXene. The introduction of MXene filled gaps and insulating regions created by pyrolyzed PVA, providing conductive pathways that resulted in a substantial increase in conductivity. In conclusion, incorporating MXene into PVA via electrospinning not only increased the contact surface area but also enhanced the amorphous characteristics and conductivity of the composite material through pyrolysis. These improvements render it highly suitable for various applications, including supercapacitors, biomedical fields, and electromagnetic interference (EMI) shielding. Declarations Conflict of Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper. Ethical approval Not applicable Author contribution Aparna Zagabathuni : Conceptualization, Methodology, Writing - review & editing, and Supervision. VP Muhammad Rabeeh : Formal analysis, Project administration, Investigation, Data curation, and Writing - original draft & editing. 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A highly sensitive wearable pressure sensor capsule based on PVA/Mxene composite gel. 3 biotech. 2022 Jul 13;12(8). Liu R, Li W. High-Thermal-Stability and High-Thermal-Conductivity Ti 3 C 2 T x MXene/Poly(vinyl alcohol) (PVA) Composites. ACS Omega. 2018 Mar 5;3(3):2609–17. Haq YU, Ullah R, Mazhar S, Khattak R, Qarni AA, Haq ZU, et al. Synthesis and characterization of 2D MXene: Device fabrication for humidity sensing. Journal of Science: Advanced Materials and Devices. 2021 Aug;7(1). Cite Share Download PDF Status: Published Journal Publication published 17 Apr, 2025 Read the published version in Journal of Polymer Research → Version 1 posted Reviewers agreed at journal 08 Dec, 2024 Reviewers invited by journal 13 Nov, 2024 Editor invited by journal 29 Oct, 2024 Editor assigned by journal 23 Oct, 2024 First submitted to journal 22 Oct, 2024 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-5316740","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":377890140,"identity":"478bd8e6-a4bb-4fe4-8da0-7def62e93c28","order_by":0,"name":"Aparna Zagabathuni","email":"data:image/png;base64,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","orcid":"","institution":"NITC: National Institute of Technology Calicut","correspondingAuthor":true,"prefix":"","firstName":"Aparna","middleName":"","lastName":"Zagabathuni","suffix":""},{"id":377890141,"identity":"365dbfe7-3fa4-4fdf-b63e-d0a87ce70d19","order_by":1,"name":"VP Rabeeh","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"VP","middleName":"","lastName":"Rabeeh","suffix":""},{"id":377890142,"identity":"4548921f-fe7b-485b-bcc8-6938eb92827c","order_by":2,"name":"Sree Pranavi G","email":"","orcid":"","institution":"","correspondingAuthor":false,"prefix":"","firstName":"Sree","middleName":"Pranavi","lastName":"G","suffix":""}],"badges":[],"createdAt":"2024-10-23 07:44:00","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-5316740/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-5316740/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1007/s10965-025-04382-4","type":"published","date":"2025-04-17T15:57:43+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":71166656,"identity":"af110f2c-a1e7-4b81-954e-0abdb33d28f1","added_by":"auto","created_at":"2024-12-11 17:49:52","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":146503,"visible":true,"origin":"","legend":"\u003cp\u003eXRD pattern of MAX phase, Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e and delaminated Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-5316740/v1/188c7b93aac839f30f833dc7.png"},{"id":71166655,"identity":"ab66eab3-801a-436a-8428-c9316cd36a39","added_by":"auto","created_at":"2024-12-11 17:49:51","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":773834,"visible":true,"origin":"","legend":"\u003cp\u003eThe SEM image of the a) MAX phase and b) delaminated Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e MXene\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-5316740/v1/ed5bea6b13a4b24e4f81b4b4.png"},{"id":71166492,"identity":"baea3da9-b7a6-4f67-8b6a-53bc9b86a7a3","added_by":"auto","created_at":"2024-12-11 17:41:51","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":402644,"visible":true,"origin":"","legend":"\u003cp\u003eCharacterization PVA electrospun fiber. a) XRD of PVA powder, as-spun PVA fiber, and pyrolyzed PVA fiber. b) SEM image of as-spun PVA fiber along with size distribution. c) SEM image of pyrolyzed PVA fiber with size distribution.\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-5316740/v1/61007dff48aa166a92ae6170.png"},{"id":71166497,"identity":"2f538eb9-8d0e-4f6b-bfa0-596dd9ec0b8d","added_by":"auto","created_at":"2024-12-11 17:41:52","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":303895,"visible":true,"origin":"","legend":"\u003cp\u003eFTIR spectra of PVA powder, as-spun PVA fiber, and pyrolyzed PVA fiber. b) Raman spectrum of as-spun PVA fiber and pyrolyzed PVA fiber\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-5316740/v1/5adb7ae8ccb405f6492fb4a7.png"},{"id":71166494,"identity":"1ed05095-995d-4c5b-9450-d8edd3a0fd97","added_by":"auto","created_at":"2024-12-11 17:41:51","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":225074,"visible":true,"origin":"","legend":"\u003cp\u003ea) XRD of PVA powder, PVA-MXene fiber, and pyrolyzed PVA-MXene fiber b) SEM image of PVA-Mxene, Histogram of PVA-Mxene c) SEM image of PVA-Mxene pyrolyzed, Histogram of PVA-Mxene pyrolyzed\u003c/p\u003e","description":"","filename":"floatimage5.png","url":"https://assets-eu.researchsquare.com/files/rs-5316740/v1/8403df368844c0ac8bef3d76.png"},{"id":71166652,"identity":"edabbb0b-86e2-4cb6-8e5d-0157f6a0ddc0","added_by":"auto","created_at":"2024-12-11 17:49:51","extension":"jpeg","order_by":6,"title":"Figure 6","display":"","copyAsset":false,"role":"figure","size":71980,"visible":true,"origin":"","legend":"\u003cp\u003ea) The FTIR spectroscopy of PVA, PVA-MXene and PVA-MXene dried b) Raman spectrum of as-spun PVA-MXene and pyrolyzed PVA-MXene.\u003c/p\u003e","description":"","filename":"floatimage6.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5316740/v1/78ce561dc5a64b9f1e55e883.jpeg"},{"id":71166653,"identity":"3dc2f5ed-54b8-4c51-9c77-5ae0a0e08ab7","added_by":"auto","created_at":"2024-12-11 17:49:51","extension":"jpeg","order_by":7,"title":"Figure 7","display":"","copyAsset":false,"role":"figure","size":119534,"visible":true,"origin":"","legend":"\u003cp\u003eCharacterization results of As-spun PVA and PVA MXene a) XRD pattern b) FTIR c) Raman spectroscopy d) electrical conductivity\u003c/p\u003e","description":"","filename":"floatimage7.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5316740/v1/03a2dec762c3a3bf4ceddb9f.jpeg"},{"id":71166654,"identity":"6fb7a0f3-91f4-4eea-a83e-7f26e1e75e69","added_by":"auto","created_at":"2024-12-11 17:49:51","extension":"jpeg","order_by":8,"title":"Figure 8","display":"","copyAsset":false,"role":"figure","size":119499,"visible":true,"origin":"","legend":"\u003cp\u003eCharacterisation results of pyrolyzed PVA and PVA MXene a) XRD pattern b) FTIR of dried PVA and PVA MXenes c) Raman spectroscopy d) electrical conductivity\u003c/p\u003e","description":"","filename":"floatimage8.jpeg","url":"https://assets-eu.researchsquare.com/files/rs-5316740/v1/bbf0205affeecdbce13b068a.jpeg"},{"id":81050877,"identity":"080cef7a-6049-4aa6-be23-8d6cebad1f2b","added_by":"auto","created_at":"2025-04-21 16:06:21","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2842177,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-5316740/v1/57517052-7e09-4541-a5c4-70a11cfe39ce.pdf"}],"financialInterests":"","formattedTitle":"Development of MXene-Enhanced Polyvinyl Alcohol Nanofibers: A Comprehensive Study on Synthesis and Characterization","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003eMXenes, a remarkable class of two-dimensional (2D) transition metal carbides or nitrides, have gained significant interest in recent years due to their unique properties. These metal layered 2D materials are synthesized through selective etching from their parent MAX phase. The reduction dimensions in MXenes exhibit significantly enhances properties not found in their bulk counterparts, making them suitable for a wide range of applications, including electronics, optoelectronics, and catalysis [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eHowever, similar to other 2D materials, MXenes tend to stack and aggregate \u0026ldquo;face-to-face\u0026rdquo; due to strong van der Waals forces, which can severely hinder their performance in practical applications [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. To address this issue, various methods have been developed to prevent restacking. One common approach involves creating composites with polymers, which weakens the interplanar attraction and increases interlayer separation. Polymers when combined with MXenes, can enhance mechanical and thermal properties while preserving excellent hydrophilicity and metallic conductivity, making then ideal materials for wearable electronic devices and batteries [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eA variety of polymers including PAN [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e], PVDF [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], PVA [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e], PEO [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e], PMMA [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e], PS [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e] etc. have been utilize to make polymer MXene composites tailored for specific applications [\u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e]. Polyvinyl alcohol (PVA), known for its strong hydrophilicity, suggests that MXenes exhibit good compatibility with PVA. Electrospinning is a widely used technique for producing nanofibers with high surface area and porosity, which are essential for enhancing the performance of composite materials. Various studies have reported on the electrospinning of different polymers [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e]. For instance, Cheng.et.al. [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e] found that incorporating an MXene/AgNP composite into a PVDF solution significantly increased electrical conductivity from 40 to 1,148 \u0026micro;S/cm. This enhancement also improved the piezoelectric properties of PVDF fibers, enabling the development of self-powered, wearable electronic devices. Similarly, Tan et.al [\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] reported that PMMA/MXene nanocomposites exhibited electrical conductivity over 3000 times higher than pure PMMA (1 \u0026times; 10\u003csup\u003e\u0026minus;\u0026thinsp;14\u003c/sup\u003e to 1 \u0026times; 10\u003csup\u003e\u0026minus;\u0026thinsp;13\u003c/sup\u003e S m\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e). Additionally, Patrik.et.al [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e] noted that PVA nanofibers containing 0.14 wt.% Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003eT\u003csub\u003ex\u003c/sub\u003e demonstrated a DC conductivity of 0.8 mS cm\u003csup\u003e-1\u003c/sup\u003e superior to that of similar composites prepared using other methods.\u003c/p\u003e \u003cp\u003eYunyun.et.al [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e] reported that adding MXene to polymer at very low concentration (0.0001 wt %- 0.002 wt %) suppressed space charge within polymeric units. This reduced filler concentration improved compatibility and dispersion at the interface while minimizing negative impacts on PVA\u0026rsquo;s physical performance. Sutasinpromprae et al. [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e] identified that internal and surface flaws introduced during heat treatment govern the tensile strength of fibers.\u003c/p\u003e \u003cp\u003eThey synthesized carbon fibres from PAN through electrospinning followed by pyrolysis. At controlled high-temperatures, the non-conductive polymer undergoes thermal decomposition to form a carbonized structure that facilitates charge carrier transfer across the film. Moreover, pyrolysis also improves thermal stability and chemical resistance. [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e][\u003cspan citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e][\u003cspan citationid=\"CR19\" class=\"CitationRef\"\u003e19\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn the present study, we explore the synthesis of PVA-MXene based fibers through electrospinning followed by pyrolysis. We aim to investigate the structural, morphological, and electrical properties of these fibers to assess their suitability for various applications.\u003c/p\u003e"},{"header":"2. Materials and Methods","content":"\u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e2.1 Preparation of Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e MXene\u003c/h2\u003e \u003cp\u003eTi\u003csub\u003e3\u003c/sub\u003eAlC\u003csub\u003e2\u003c/sub\u003e (Aritech Chemazone Pvt. Ltd.) was employed to synthesize Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e nanoflakes (NFs) through exfoliation, adhering to the procedure outlined by Lipatov et.al. [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. Initially, 1 g of LiF was dissolved in 20 mL of 6 M HCl solution, and then 1 g of Ti\u003csub\u003e3\u003c/sub\u003eAlC\u003csub\u003e2\u003c/sub\u003e was gradually introduced over a 10 min period to minimize initial overheating resulting from the exothermic reaction. Subsequently, the temperature was raised to 35\u0026deg;C, and the reaction was maintained with continuous stirring at 550 rpm for 48 hours. After repeated washing with deionized water, the pH of the resulting MXene powder was neutral. The product was collected via vacuum-assisted filtration with a PVDF membrane and subsequently dried in a vacuum desiccator at room temperature for 24 hours.\u003c/p\u003e \u003cp\u003eTo achieve further delaminate, the Ti\u003csub\u003e3\u003c/sub\u003eAlC\u003csub\u003e2\u003c/sub\u003e solution was centrifuged at 3500 rpm for 1 h, discarding the supernatant. A colloidal solution of MXene was collected from the bottom of the vial. The resulting Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e NFs were characterized by X-ray diffractometer (XRD) (PANalatical Xpert3 Powder) and a field emission scanning electron microscope (FE-SEM) (Hitachi SU-6600).\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e2.2 Preparation of PVA fiber\u003c/h2\u003e \u003cp\u003ePolyvinyl alcohol (PVA) (Thermo Fisher Scientific India Pvt. Ltd, MW 125 g/mol, degree of hydrolysis 85\u0026ndash;89%) was utilized as the primary material for the synthesis of nanofibers. The PVA solution was prepared by gradually adding 5 g of PVA powder to 50 ml of deionized water to prevent lump formation. The mixture was continuously agitated for 3 hours, during which the temperature was gradually increased to 90\u0026deg;C while maintaining a stirring speed of 1500 rpm. The prepared solution was carefully transferred into a 12 ml syringe, ensuring the absence of air bubbles. The syringe was then positioned into the electrospinning apparatus, specifically the Holmarc-model HO-NFES-043. A voltage of 15 kV was applied between the needle and the mandrel, with the needle serving as the positive terminal and the mandrel as the negative terminal. The flow rate was adjusted to 0.2 ml per hour, and the distance between the needle and the mandrel was maintained at 12 cm. Electrospinning was conducted for a duration of 6 hours to obtain a coherent nanofiber mat on the mandrel.\u003c/p\u003e \u003cp\u003eFollowing electrospinning, the developed fibers were carefully peeled from the mandrel and subjected to hydrolysis by heating at 155\u0026deg;C for 6 hours, resulting in partial dehydration [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. The hydrolysed sample was subsequently subjected to pyrolysis in a tubular furnace at 800\u0026deg;C with a heating rate of 10\u0026deg;C/min. The samples were maintained at this temperature for 90 minutes in an argon atmosphere. The sample that underwent hydrolysis was designated as PVA-dried, whereas the sample subjected to pyrolysis was labelled as PVA pyro.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e2.3 Preparation of PVA-MXene nanofibers\u003c/h2\u003e \u003cp\u003e80 mg of MXene NFs were added to 50 ml of the PVA solution prepared as described in section \u003cspan refid=\"Sec4\" class=\"InternalRef\"\u003e2.2\u003c/span\u003e, resulting in a 0.016 wt % MXene solution. The PVA-MXene solution was then subjected to magnetic stirring at a rotational speed of 1500 rpm for 24 hours to ensure uniformity and consistent mixing. After stirring, the solution was carefully transferred into a 12 ml syringe, taking care to avoid the formation of air bubbles. Electrospinning was conducted using the same parameters outlined in section \u003cspan refid=\"Sec4\" class=\"InternalRef\"\u003e2.2\u003c/span\u003e. Once the electrospinning process was complete, the fibers were peeled from the mandrel and underwent multiple stages of heat treatment, as described in Section \u003cspan refid=\"Sec4\" class=\"InternalRef\"\u003e2.2\u003c/span\u003e. The samples that underwent hydrolysis was designated as PVA-MXene-dried, while the sample that underwent pyrolysis was labelled PVA-MXene-pyro.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e2.4 Test Characterization\u003c/h2\u003e \u003cp\u003eThe morphological characteristics of the as-spun and heat-treated samples, referred to as HT samples, were characterized using field emission scanning electron microscopy (FE-SEM). XRD analysis was conducted over the range of 2θ\u0026thinsp;=\u0026thinsp;5\u0026deg; to 60\u0026deg; with a step size of 0.15\u0026deg;. To identify the functional groups, present, Fourier transform infrared spectrometer (FTIR, PerkinElmer Frontier) was employed. Additionally, Raman spectroscopy (Horiba Lab Ram-HR Evolution confocal Raman spectrometer) measurements were taken using a diode-pumped solid-state laser with a wavelength of 532 nm, capturing absortion spectra in the range of 200\u0026ndash;1200 cm\u003csup\u003e\u0026ndash;1\u003c/sup\u003e. Conductivity measurements of the electrospun PVA and PVA-MXene samples were performed on a carbon fiber mat to ensure a continuous conductive path for accurate conductivity assessment. The pyrolyzed samples coated on the carbon fiber mat were designated as pyrolyzed CF, pyrolyzed CF-PVA and pyrolyzed CF-PVA-MXene. An LCR meter (HIOKI IM-3536) was utilized for these measurements, employing four probes with frequencies ranging from 1 kHz to 1 MHz. The samples for conductivity measurement were specifically prepared by electrospinning PVA and PVA-MXene onto the carbon fiber mat, facilitating a continuous conductive path for the conductivity evaluation.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results and Discussions","content":"\u003cdiv id=\"Sec8\" class=\"Section2\"\u003e \u003ch2\u003e3.1 Characterization of MXenes\u003c/h2\u003e \u003cp\u003eThe X-ray diffraction patterns of the Ti\u003csub\u003e3\u003c/sub\u003eAlC\u003csub\u003e2\u003c/sub\u003e MAX phase, exfoliated Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e MXene, and delaminated Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e MXene NFs are shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e. The as-purchased MAX phase predominantly consisted of the Ti\u003csub\u003e3\u003c/sub\u003eAlC\u003csub\u003e2\u003c/sub\u003e phase. Following etching with LiF and HCl, it was evident that all peaks in the MXene data, except for the (002) and (104) peaks, nearly vanished. Notably, the (002) peak exhibited a downward shift in angle from 9.5\u0026deg; to 6.5\u0026deg;, indicating the selective etching of aluminium from the MAX phase. Additionally, the full width at half maximum (FWHM) of the (002) peak increased from 0.23 to 0.63 during the etching process. After delamination, the (104) peak diminished, further confirming the two-dimensional nature of the obtained Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e MXene NFs [\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e]. The d-spacing after delamination was measured to be 14.39 A˚.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e presents SEM images illustrating the morphological characteristics of the Ti\u003csub\u003e3\u003c/sub\u003eAlC\u003csub\u003e2\u003c/sub\u003e MAX phase and Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e MXene. The delamination of the Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e MXene is specifically highlighted in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e (b). The analysis revealed the presence of a characteristic accordion-like shape and cross-sectional shear slip in the multilayer MXenes, providing compelling evidence for the successful delamination of Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003e [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e3.2 Characterisation of PVA-nanofibers\u003c/h2\u003e \u003cp\u003eThe electrospinning process for producing defect-free fibers is influenced significantly by the molecular weight and concentration of the polymer solution. To achieve smooth, bead-free fibers, it is essential to use the polymer solution with a concentration of atleast 10 wt.% polyvinyl alcohol (PVA) [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. At this optimized PVA concentration, the solution forms a stretchable network of PVA chains, which helps prevent network rupture during the electrospinning process. The morphology and distribution of the fiber diameter for each obtained mat are illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e(b) and (c).\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e (a) represents the XRD patterns for PVA powder, PVA nanofiber, and pyrolyzed PVA nanofibers. The XRD pattern of pure PVA powder shows peaks at 2θ\u0026thinsp;=\u0026thinsp;20\u0026deg; and 2θ\u0026thinsp;=\u0026thinsp;40.5\u0026deg;, corresponding to the \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{(1}00)\\)\u003c/span\u003e\u003c/span\u003e and \u003cspan class=\"InlineEquation\"\u003e\u003cspan class=\"mathinline\"\u003e\\(\\:\\stackrel{-}{(1}11)\\)\u003c/span\u003e\u003c/span\u003e crystallographic planes of PVA, respectively. These peaks indicate the semi-crystalline nature in pure PVA and suggest polymer chain alignment due to hydrogen bonding [\u003cspan citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e]. However, after the electrospinning process, these peaks vanished, leaving only a single broad peak around 2θ\u0026thinsp;=\u0026thinsp;20\u0026deg;, suggesting a transition to a predominantly amorphous structure with significantly reduced crystallinity. Despite being a semi-crystalline polymer, the rapid solidification of the polymer fluid during the electrospinning process is the cause of the lack of crystallinity in the as-spun fibers [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. A broad peak around 2θ\u0026thinsp;=\u0026thinsp;24\u0026deg; in PVA-fiber-pyrolyzed, corresponding to the (002) crystallographic plane, suggests significant structural transformations. This peak likely arises from weak intermolecular interaction of the -OH groups in the PVA, which leads to the disruption of its original linear ordered structure and facilitates a transformation into a ladder-like polymeric structure. Such changes indicate the formation of extremely tiny and randomly organized pseudo-graphite layers, consistent with disordered micrographite stacking [\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAt the optimum PVA concentration, the polymer solution formed a flexible network of interconnected PVA chains, effectively preventing fiber rupture during electrospinning. Figure\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e(b) presents the SEM micrographs and the corresponding fiber distribution for the PVA electrospun mat. This shows that the randomly aligned fibers were characterized by a size distribution spanning from 40 to 280 nm. The average diameter of these fibers, determined through image-J analysis, was found to be 235 nm. During hydrolysis, an increase in temperature led to partial melting of the fibers, resulting in structural changes such as fiber merging, fusion, and alterations in surface texture. These changes induced dynamic crystallization and recrystallization in the melted zones, as illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e(c). The pyrolyzed fibers displayed in the Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e(c) also exhibited random orientation and a broad size distribution, ranging from 25 to 275 nm.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe primary chemical composition of PVA is represented by the repeating unit \u0026ndash; (CH\u003csub\u003e2\u003c/sub\u003e\u0026ndash;CHOH)\u003csub\u003en\u003c/sub\u003e with the individual building block being (CH\u003csub\u003e2\u003c/sub\u003e\u0026thinsp;=\u0026thinsp;CHOH). The FTIR spectrum analysis presented in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e(a) highlight the prominent peaks related to PVA. Notably, peaks located around 2000 cm\u003csup\u003e\u0026ndash;1\u003c/sup\u003e in all three spectra are attributed to C-H bond bending. The spectral characteristics of the electrospun PVA fibers closely resemble those of the PVA powder, albeit with slight variations in relative intensity and peak position. The -OH stretching of electrospun PVA, observed at 3278 cm\u003csup\u003e-1\u003c/sup\u003e, remains unchanged in its position as compared to PVA powder. However, it becomes broader in PVA dried due to the hydrolysis process, suggesting the elimination of water molecules [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e]. Substantial fluctuations noted in the carbonyl stretching region between 1700 cm\u003csup\u003e\u0026ndash;1\u003c/sup\u003e to 1735 cm\u003csup\u003e\u0026ndash;1\u003c/sup\u003e for the PVA fiber compared to the PVA powder. A more profound dip at 1711 cm\u003csup\u003e\u0026ndash;1\u003c/sup\u003e is identified in the PVA dried, indicating the formation of carbonyl groups as a result of hydrolysis, which involves the elimination of water and subsequent chain reactions. Additionally, the asymmetric stretching band of -CH\u003csub\u003e2\u003c/sub\u003e at 2935 cm\u003csup\u003e-1\u003c/sup\u003e develops a shoulder in the PVA dried compared to PVA powder and PVA fibers. The C\u0026thinsp;=\u0026thinsp;C stretching mode of PVA is associated with the band at 1143 cm\u003csup\u003e-1\u003c/sup\u003e, which is crystalline sensitive [\u003cspan citationid=\"CR25\" class=\"CitationRef\"\u003e25\u003c/span\u003e]. A notanble reduction of this peak is observed in the PVA fiber when compared to PVA powder, indicating a transition from crystalline to amorphous structure. Furthermore, a greater dip in this peak for the PVA dried suggests the development of a ladder-like structure.\u003c/p\u003e \u003cp\u003eThe Raman spectra of the as-spun PVA fiber and pyrolyzed PVA fibers are presented in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e(b). In the spectrum of the as-spun PVA, the most prominent scattering peaks corresponding to the stretching vibrations of -CH\u003csub\u003e2\u003c/sub\u003e and -CH groups, with a peak at 1440 cm\u003csup\u003e-1\u003c/sup\u003e is attributed to the stretching vibrations of -CH and -OH within the PVA molecules. Following pyrolysis, two peaks appeared at 1334 cm\u003csup\u003e-1\u003c/sup\u003e and 1585 cm\u003csup\u003e-1\u003c/sup\u003e, corresponding to the D (characteristic of a disordered sp\u003csup\u003e3\u003c/sup\u003e phase) and G bands (characteristic of the in-plane stretching vibration mode E\u003csub\u003e2g\u003c/sub\u003e of well-crystallized graphite) respectively. The defect density in carbon nanostructures is typically quantified by the intensity ratio between the D and G bands (I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e). The (I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e) ratio for pyrolyzed PVA is 1.904. This higher I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e suggests an increased level of disorder and defects within the material, which can be indicative of amorphous carbon.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e(a) displays the XRD patterns of the three samples: PVA powder, PVA-MXene fiber, and pyrolyzed PVA-MXene fiber. The electrospun PVA-MXene fiber exhibits a prominent amorphous peak at 2θ\u0026thinsp;=\u0026thinsp;20\u0026deg;, indicating the absence of a crystalline phase and confirming its amorphous nature. After pyrolysis at 800\u0026deg;C, the peak at 2θ\u0026thinsp;=\u0026thinsp;20\u0026deg; disappears, and a broad peak around 2θ\u0026thinsp;=\u0026thinsp;24\u0026deg; emerges. The diffraction peak in the XRD pattern of the pyrolyzed PVA-MXene fiber is attributed to the (002) crystallographic plane of graphite.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e(b) presents the SEM image depicting the surface morphology and diameter of the fabricated nanofibers. Node-like lumps began to appear in the PVA-MXene fibers, indicating structural changes. The fibers exhibited a random orientation with a broad diameter distribution ranging from 140 nm to 300 nm. During the hydrolysis process at 195\u0026deg;C, further changes in fiber structure occurred, including merging and fusion among fibers, as well as alteration in surface texture. These modifications resulted in dynamic crystallization and recrystallization in the melted zone, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e(c). Additionally, a random distribution of fibers was observed, with diameters ranging from 100 to 220 nm, and the average diameter was determined to be 198 nm.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe FTIR spectra of PVA-MXene, PVA-MXene dried, and PVA were analyzed in the range of 400\u0026ndash;5000 cm\u003csup\u003e-1\u003c/sup\u003e, as shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e(a). Common peaks at 2935 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 1143cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 3278 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and 1090 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, were observed in all three spectra [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e][\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e]. The -OH stretching associated with hydrolysis is visible at 3278 cm\u003csup\u003e-1\u003c/sup\u003e in the absorption peak of PVA MXene, resulting from intermolecular hydrogen bonding. Symmetric C-H bonding and -CH\u003csub\u003e2\u003c/sub\u003e bending are evident at 2935 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e and 1143 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, respectively. Additionally, a peak corresponding to C\u0026ndash;O stretching was observed in the PVA spectrum. Although MXene-influenced peaks are not prominently reflected in the graph, some shoulder peaks are noted between 300 cm\u003csup\u003e-1\u003c/sup\u003e-500 cm\u003csup\u003e-1\u003c/sup\u003e in the spectrum of PVA MXene pyrolyzed. These shoulders may arise from bond-breaking processes during hydrolysis. The presence of similar contours across the spectra confirms that physical interactions between PVA and Mxene were observed.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig6\" class=\"InternalRef\"\u003e6\u003c/span\u003e(b) illustrates the Raman spectra of both pyrolyzed and as-spun PVA-MXene fibers. The most prominent scattering peak at 1440 cm\u003csup\u003e-1\u003c/sup\u003e in the spectrum of as-spun PVA-MXene corresponds to the stretching vibrations of -CH and -OH groups in the PVA molecules. After pyrolysis, two new peaks appeared at 1334 and 1585 cm\u003csup\u003e-1\u003c/sup\u003e, which are associated with the D and G bands, respectively [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. The (I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e) ratio for pyrolyzed PVA-MXene is measured at 1.293. This reduction in defect density, indicated by a decrease in the (I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e) ratio, suggests that the pyrolyzed PVA-MXene possesses a more crystalline structure.\u003c/p\u003e \u003cp\u003eIn Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e(a), peak broadening and a decrease in intensity at 2θ\u0026thinsp;=\u0026thinsp;20\u0026deg; are observed in the XRD patterns of both as-spun PVA and as-spun PVA-MXene fibers. This indicates an increase in the amorphous nature of the fibers upon the addition of MXene. In the FTIR spectra of the as-spun fibers, shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e(b), only minor differences are noted when the MXene concentration is very low, specifically at 0.016 wt.%. Notably, an additional dip at 1087 cm\u003csup\u003e-1\u003c/sup\u003e, corresponding to C\u0026thinsp;=\u0026thinsp;O stretching, is attributed to the presence of MXene [\u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. Furthermore, a small but broad dip at 3278 cm\u003csup\u003e-1\u003c/sup\u003e, associated with O-H stretching, is caused by inter- and intra-molecular hydrogen bonding.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe Raman spectroscopic analysis of the as-spun PVA and PVA-MXene fibers, shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e(c), reveals no significant differences in the corresponding characteristic peaks. However, several peaks, specifically the Eg and Ag modes associated with MXene, appear as shoulders below 700 cm\u003csup\u003e-1\u003c/sup\u003e upon the addition of MXene.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig7\" class=\"InternalRef\"\u003e7\u003c/span\u003e(d) presents the electrical conductivity results for the as-spun fibers of PVA and PVA-MXene spun on carbon fibers. The data indicate frequency independence in the lower frequency ranges, followed by a consistent and progressive increase in conductivity as frequency rises. This behaviour can be attributed to the presence of PVA, while the enhanced conductivity is primarily due to the incorporation of MXene. MXene facilitates a conductive pathway that integrates into the woven mat during the electrospinning process within the polymer matrix, further enhancing overall conductivity.\u003c/p\u003e \u003cp\u003eIn Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e(a), the XRD results for pyrolyzed PVA and PVA-MXene show very broad peaks, indicating their amorphous nature. The broadness observed in PVA-MXene is greater than that in PVA, which is attributed to its amorphous structure, making it potentially more suitable for battery applications. The FTIR spectral analysis of PVA dried PVA and PVA-MXene, depicted in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e(b), shows similarities between peaks at 2935 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, 3278 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, and 1711 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e in both samples. However, there is a noticeable decrease in peak sharpness for PVA-MXene compared to the as-spun sample, suggesting structural degradation upon heating to 195 ˚C. In contrast, the appearance of these same peaks in dried PVA indicates an increase in crystallinity. Additionally, a small amount of shoulder formation is observed below 500 cm\u003csup\u003e\u0026minus;\u0026thinsp;1\u003c/sup\u003e, which is attributed to MXenes.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn the Raman spectroscopic analysis of pyrolyzed PVA and PVA-MXene, shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e(c), the I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e ratios were found to be 1.294 and 1.904, respectively. This difference in the I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e ratio indicates a higher defect density and an increase in the amorphous nature of the PVA-MXene sample, which aligns with the findings from the XRD analysis.\u003c/p\u003e \u003cp\u003eFigure \u003cspan refid=\"Fig8\" class=\"InternalRef\"\u003e8\u003c/span\u003e(d) compares the electrical conductivities of the pyrolyzed samples with those of pyrolyzed carbon fibers. The conductivity of the pyrolyzed CF-PVA sample was lower than that of the pyrolyzed CF sample. PVA, which is originally a dielectric material, undergoes degradation and structural changes during pyrolysis, potentially diminishing the continuous electrical pathways provided by carbon fibers. These insulating regions within the composite hinder electron transport. In contrast, the presence of MXene in pyrolyzed CF-PVA-MXene facilitated electron transport by creating conductive pathways in the voids left by the PVA. As a result, a significant improvement in conductivity was observed [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003c/div\u003e"},{"header":"4. Conclusion","content":"\u003cp\u003ePVA-MXene based fibers were successfully synthesized through an electrospinning process and subsequently pyrolyzed to enhance conductivity. X-Ray diffraction analysis revealed the amorphous nature of both the as-spun PVA and PVA-MXene samples, indicated by the presence of broader peaks that signify a lack of long-range order in their structure. The increasing broadness and shoulder formation in the peak at 2θ\u0026thinsp;=\u0026thinsp;24\u0026deg; for the pyrolyzed PVA-MXene sample further confirmed its suitability for battery applications. The SEM results provided insight into the morphological properties of the electrospun fibers, which exhibited increased surface area and, consequently, a higher number of active sites. The average diameter of the PVA fibers was measured at 235 nm, however, upon the addition of MXene, this diameter decreased to 198 nm, facilitating improved transport properties. FTIR analysis confirmed the presence of MXenes encapsulated within the polymer matrix of the PVA fiber mat. The elimination of certain peaks during heat treatment indicated structural deformations leading to carbonization. The I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e ratios obtained from Raman spectroscopy suggested that the presence of MXenes improved defect density in PVA while enhancing its amorphous characteristics. Additionally, electrical conductivity results demonstrated a significant impact from the incorporation of MXene. The introduction of MXene filled gaps and insulating regions created by pyrolyzed PVA, providing conductive pathways that resulted in a substantial increase in conductivity.\u003c/p\u003e \u003cp\u003eIn conclusion, incorporating MXene into PVA via electrospinning not only increased the contact surface area but also enhanced the amorphous characteristics and conductivity of the composite material through pyrolysis. These improvements render it highly suitable for various applications, including supercapacitors, biomedical fields, and electromagnetic interference (EMI) shielding.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e \u003ch2\u003eConflict of Interest\u003c/h2\u003e \u003cp\u003eThe authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.\u003c/p\u003e \u003c/p\u003e\u003cp\u003e \u003ch2\u003eEthical approval\u003c/h2\u003e \u003cp\u003eNot applicable\u003c/p\u003e \u003c/p\u003e\u003ch2\u003eAuthor contribution\u003c/h2\u003e \u003cp\u003e \u003cb\u003eAparna Zagabathuni\u003c/b\u003e: Conceptualization, Methodology, Writing - review \u0026amp; editing, and Supervision. \u003cb\u003eVP Muhammad Rabeeh\u003c/b\u003e: Formal analysis, Project administration, Investigation, Data curation, and Writing - original draft \u0026amp; editing. \u003cb\u003eG Sree Pranavi\u003c/b\u003e: Conceptualization, Methodology, Formal analysis, Project administration, Investigation, Validation, Data curation, and Writing - original draft\u003c/p\u003e\u003ch2\u003e5. Acknowledgement\u003c/h2\u003e \u003cp\u003eThe authors would like to thank the Centre for Materials Characterization (CMC) at NIT Calicut for providing the Raman and XRD facilities. This work was not funded by any agency.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eKhan K, Tareen AK, Aslam M, Wang R, Zhang Y, Mahmood A, et al. Recent developments in emerging two-dimensional materials and their applications. Journal of Materials Chemistry C. 2020;8(2):387\u0026ndash;440.\u003c/li\u003e\n\u003cli\u003eWu Z, Shang T, Deng Y, Tao Y, Yang Q. The Assembly of MXenes from 2D to 3D. Advanced Science. 2020 Feb 13;7(7):1903077.\u003c/li\u003e\n\u003cli\u003eLing Z, Ren CE, Zhao MQ, Yang J, Giammarco JM, Qiu J, et al. Flexible and conductive MXene films and nanocomposites with high capacitance. 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Journal of Science: Advanced Materials and Devices. 2021 Aug;7(1).\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-polymer-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jpol","sideBox":"Learn more about [Journal of Polymer Research](https://www.springer.com/journal/10965)","snPcode":"10965","submissionUrl":"https://www.editorialmanager.com/jpol/","title":"Journal of Polymer Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"polymer-MXene composite, nanofibers, pyrolysis, electrical conductivity","lastPublishedDoi":"10.21203/rs.3.rs-5316740/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-5316740/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe integration of two-dimensional materials into polymer matrices has garnered significant attention in recent years due to potential to enhance the mechanical and electrical properties of composite materials. This study focuses on synthesizing polyvinyl alcohol (PVA) and Ti\u003csub\u003e3\u003c/sub\u003eC\u003csub\u003e2\u003c/sub\u003eT\u003csub\u003ex\u003c/sub\u003e MXene into a nonwoven nanofiber (NF) composite mat using an electrospinning. Following the electrospinning process, the fibers underwent pyrolysis, a crucial step that enhances their electrical conductivity and structural integrity. To characterize the nanofibers, an X-ray diffraction (XRD), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), and field emission scanning electron microscopy (SEM) were performed. XRD and FTIR analysis confirmed the presence of both PVA and MXene, while SEM revealed improved morphological properties, including increased surface area and a higher number of active sites. The Raman spectra provided insights into defect densities, with the I\u003csub\u003eD\u003c/sub\u003e/I\u003csub\u003eG\u003c/sub\u003e ratio indicating that the incorporation of MXene and subsequent pyrolysis effectively increased defect density in PVA while enhancing its amorphous nature. Importantly, electrical conductivity measurements demonstrated a substantial enhancement in direct current conductivity for the pyrolyzed PVA-MXene composite fibers. The improved defect densities created an additional pathway for charge carriers through localized stress distribution, leading to higher conductivity.\u003c/p\u003e","manuscriptTitle":"Development of MXene-Enhanced Polyvinyl Alcohol Nanofibers: A Comprehensive Study on Synthesis and Characterization","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2024-12-11 17:41:47","doi":"10.21203/rs.3.rs-5316740/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"reviewerAgreed","content":"","date":"2024-12-08T18:46:43+00:00","index":0,"fulltext":""},{"type":"reviewersInvited","content":"","date":"2024-11-14T01:34:30+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"Journal of Polymer Research","date":"2024-10-29T12:31:36+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2024-10-24T00:33:38+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Polymer Research","date":"2024-10-23T03:42:35+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-polymer-research","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"jpol","sideBox":"Learn more about [Journal of Polymer Research](https://www.springer.com/journal/10965)","snPcode":"10965","submissionUrl":"https://www.editorialmanager.com/jpol/","title":"Journal of Polymer Research","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"em","reportingPortfolio":"Springer Hybrid","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"b8e64ea5-3fd9-42f0-a2b1-140a00139d86","owner":[],"postedDate":"December 11th, 2024","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[],"tags":[],"updatedAt":"2025-04-21T16:01:25+00:00","versionOfRecord":{"articleIdentity":"rs-5316740","link":"https://doi.org/10.1007/s10965-025-04382-4","journal":{"identity":"journal-of-polymer-research","isVorOnly":false,"title":"Journal of Polymer Research"},"publishedOn":"2025-04-17 15:57:43","publishedOnDateReadable":"April 17th, 2025"},"versionCreatedAt":"2024-12-11 17:41:47","video":"","vorDoi":"10.1007/s10965-025-04382-4","vorDoiUrl":"https://doi.org/10.1007/s10965-025-04382-4","workflowStages":[]},"version":"v1","identity":"rs-5316740","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-5316740","identity":"rs-5316740","version":["v1"]},"buildId":"qtupq5eGEP_6zYnWcrvyt","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}