Influence of ZrO2 filler on physico-chemical properties of PVA/NaClO4 polymer composite electrolytes
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Abstract
The ZrO2-filled PVA/NaClO4 polymer nanocomposite is a freestanding electrolyte film and is prepared using the solution casting method in an aqueous medium. These prepared samples were characterized for structural, morphological, optical, thermal, and electrical properties. FT Raman studies confirmed the interaction between PVA and NaClO4, and dispersion of ZrO2 fillers in the PVA/NaClO4 polymer electrolyte. The surface roughness was observed from AFM images. Fitting the values of UV absorption to Tauc’s equation, the optical energy band gaps have been evaluated and correlated to the electrical conductivity. The maximum electrical conductivity of 4.3 × 10−3 (± 0.0002) S/cm was obtained for 3 wt% ZrO2-filled PVA/NaClO4 polymer nanocomposite. The thermal degradation kinetic parameter was calculated by fitting thermo gravimetric analysis values in Broid’s model.
Possible interaction of ZrO2 filled PVA/NaClO4 reflected in Raman peaks in FT-Raman spectra
Keywords
Thermal properties Polymer nanocomposite Optical band gap Kinetics ZrO21 Introduction
There were many large volumes of articles published about polymer nanocomposite; despite that, the understanding of changes in their basic physical properties due to insertion of nanofillers remains unanswered. This is because of the complexity of polymer nanocomposite and lack of sufficient experimental data. The size and shape of the nanoparticles as well as state of dispersion in the polymer matrix have a large impact on the properties of a polymer nanocomposite. In some cases, it is difficult to obtain uniform dispersions, which results in variations in properties for systems of the same composition prepared using different techniques [1]. To generalize, understanding the variation in the basic properties of polymer nanocomposites requires investigation of various compositions under various conditions. The field of polymer nanocomposites has been one of the most popular current research areas for the last several decades because of their wide applicability in microelectronics [2], biomaterials [3], drug delivery [4], miniemulsion particles [5], fuel cell electrode polymer bound catalysts [6, 7], layer-by-layer self-assembled polymer films [8], nanofibers [9], imprint lithography [10], polymer blends [11], sensors [12], microelectromechanical systems (MEMS) [13], and photovoltaics [14]. Incorporation of inorganic nanoparticles in a polymer matrix has attracted attention due to their new physical–chemical properties, differing from the polymer matrix and the nanoparticles [15]. This kind of behavior of nanocomposites has opened their applications in the various areas listed above.
Among the different nanofillers, metal oxides have become important candidates due to their potentially unique optical, electronic, mechanical, and structural characteristics [16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26]. Zirconia (ZrO2) is one of the important metal oxides for this purpose; it has three crystal forms monoclinic, tetragonal, and cubic, and good mechanical and thermal resistance [16], high melting point, chemical stability, low electrical conductivity, high refractive index and band gap, hardness, and biocompatibility [17, 18, 19, 20, 21]. ZrO2 has been used in many applications including transparent optical devices [22], fuel cells [23], catalysts, sensors [24], microelectronics [25], ceramics, and biomaterials [18, 19, 26, 27].
Poly (vinyl alcohol) (PVA) is a water-soluble, semi-crystalline, synthetic polymer with the chemical formula [CH2CH(OH)]n. PVA is mainly used for emulsion polymerization aids, colloidal protection, textile sizing agents, architectural applications, fibers, paper coatings, and adhesives. It has gained wide application due to its excellent film casting, emulsifying, and adhesive properties; relatively high tensile strength; and good flexibility. Its thermal characteristics vary with the degree of crystallinity, which is heavily dependent on the degree of hydrolysis and the average molecular weight of the polymer. The molecular weight and tacticity of the PVA and the nature of a doping element when used play a critical role in tuning the physico-chemical properties as per application requirements [28, 29, 30].
In comparison with traditional batteries, all the solid-state metal ion batteries offer high energy densities which are very important contribution to next-generation energy storage technology. In that precept, the solid electrolytes offer new possibilities in a large-scale energy storage system for application such as electric vehicle and grid energy storage, but the research regarding solid-state electrolytes requires in-depth approach in order to enhance energy density, ionic conductivity, electrochemical stability, and mechanical property. To achieve all above properties in single electrolyte, thorough understanding of salt–polymer interaction, polymer–filler interaction, salt–filler interaction, theoretical modeling to predict the experimental results, details of the ion transport mechanism, and a concern towards the lower cost for large-scale applications is required [31]. Ideal solid polymer electrolyte, i.e., the salt/polymer combination, requires high viscosity and high ionic conductivity with other physico-chemical properties. The higher viscosity leads to lower ionic conductivity and poor cyclability at ambient temperature. One more limitation is the breakdown in electrode/electrolyte interphase due to the formation of unwanted side products during the salt–polymer interaction. It may affect the ion transport, ion polarization, and charge carrier concentration [32]. The high segmental polymer chain mobility and high number of efficient ion salt dissociation are required to get high ionic conductivity [31].
The host dry polymer matrix with sodium salt acts as a solid solvent. It is a dry system, which suffers low ionic conductivity at ambient temperature, but the addition of fillers may enhance the conductivity by decreasing the glass transition temperature. For high-capacity large-scale storage and severe safety concerned applications, sodium-based batteries are ideal, but a lack of sodium solid-state electrolytes with high ionic conductivity at ambient temperature is the demerit. Incorporation of ZrO2-like inorganic species provides new structural arrangement to the polymer matrix, leading to enhanced conductivity and mechanical properties along with a wide operating temperature range due to increase in thermal resistance of the polymer matrix [33]. The overall information regarding sodium solid polymer electrolytes encourages researchers to work in this field [31].
Even though lithium ion batteries have been successfully implemented in power electronics, sodium ions have been considered as a most appealing alternative to lithium ion due to their lower cost, most abundant availability, richer intercalation chemistry, and ease of recycling. There are many reports showing successful implementations of sodium ions in high-temperature Na/S cells for megawatt electrical storage and for Na/NiCl2 Zebra-type systems for electric vehicles, both of which take advantage of the highly conducting solid beta-alumina ceramics containing Na+ at temperatures, i.e., 300 °C [34, 35]. However, sodium ion technology needs to be focused to achieve the properties shown by lithium ions at room temperature. If it is achieved, the future electronics will be based on these low-cost, sustainable materials.
The ionic conductivity is also dependent on the kind of anion present in the salt. The conductivity is dependent on polarizability of the anion. In case of sodium salts, conductivity increment follows PF6− > ClO4− > CF3SO3−. Looking at these results, NaPF6 may be the best choice as an electrolyte, but solubility of NaPF6 is very less in comparison with NaClO4. This will reduce ion density in the composites. At higher concentrations, NaPF6 forms insoluble impurities in the electrolyte. Along with this, the higher reactivity of the NaPF6 reduces the battery performances. The NaClO4 has a relatively low anion polarization and stable cycle performance with negligible fading over 100 cycles, compared to all other sodium salts. NaClO4 has very high melting temperature of about 468 °C, which introduces higher thermal stability to the electrolyte. Looking at the wide operating temperature range, relatively high conductivity, higher thermal stability, and chemical stability of NaClO4, make one of the best choices to use it as an electrolyte for sodium ion batteries [36, 37, 38]. In that perspective, this paper is mainly focused on the preparation of polymer nanocomposites composed of PVA, NaClO4 salt, and ZrO2 filler and the study of its optical, thermal, and surface morphology and room temperature electrical conductivity properties.
2 Experimental methods
2.1 Materials used
The polymer PVA, with molecular weight 1,40,000 MW, and zirconium dioxide (ZrO2), with molecular weight 123.22 g/mol, used in this work were procured from Himedia Laboratories Pvt, Ltd., India. Sodium per chlorate (NaClO4, with molecular weight 122.44 g/mol) was purchased from Sigma-Aldrich Co. India.
2.2 Preparation of polymer nanocomposite
Preparation of ZrO2-filled PVA/NaClO4 composite films
Photographs of different concentrations of ZrO2-filled PVA/NaClO4 composite films
2.3 Characterization techniques
Fourier transform (FT) Raman spectra were measured using a Thermo Fisher Scientific Inc. (USA) model (NXR) FT Raman module spectrophotometer using Nd:YAG 1064-nm laser as an exciting source, which has 4000–40 cm−1 range of wave number and a resolution of 8 cm−1. The microstructural and optical properties were studied using a Shimadzu Co. Japan model Shimadzu UV-1800 UV–visible spectrophotometer to record the absorbance and transmittance behavior of the PVA/NaClO4 at various ZrO2 wt% in the wavelength range of 190–800 nm and the scan rate of 10 nm/min. The films for the UV–visible absorbance measurements were formed by placing 1 cm × 2 cm piece solid polymer films in a sample holder. Atomic force microscopy (AFM) was performed using nanosurf EZ2-FlexAFM in the air at an ambient condition using the dynamic force mode with a scan rate of 156 kHz and the resolution of 256 samples per line with 10 μm × 10 μm image size.
Thermo gravimetric analysis (TGA) and differential thermal analysis (DTGA) were performed on a TA Instrument Co., Inc (USA) Model Q600. The balance was calibrated with the given standards and the TGA temperature was calibrated with Curie temperature standards. To understand the kinetics of the thermal decomposition, the heating was applied at a ramp of 10 °C/min to 600 °C from 25 °C, with samplings every 0.5 s. The TGA pan was filled with a sample variance with a weight from 5 to 9 mg. Nitrogen (100 ml/min) was used as a sample purge gas for the pyrolysis experiments in the TGA unit and air was used for forced cooling after completion of degradation.
The DC conductivity studies were carried out using a Keithley instrument, USA, model Keithley 236, I-V programmable source meter, using a two-probe method at room temperature. Here, the polymer films were sandwiched between two steel electrodes and the measurements were carried out, in resistance mode, by applying voltage in the range 0–5 V; in successive steps of 0.1 V, the current was measured. Generally, the measured resistance consists of three components, i.e., Rmeasured = Rsample + Rcontact + Rwires, where Rmeasured is the resistance measured, Rsample is the sample resistance, Rcontact is the contact resistance, and Rwires is the connected wire resistance [41]. Short-length and high conducting copper wires are connected for resistance measurement so that the magnitudes of the component, Rwires, are much smaller than other terms and can be neglected. High conducting silver-coated steel electrodes and a rough surface of the sample reduce the contact resistance between electrode and electrolyte. The calculated contact resistance of the steel electrode was of the order of 10−6 Ωm, negligible compared to other terms. Considering the volume resistivity and geometry of the samples, the actual electrical resistance was calculated using the equation Rsample = (resistivity × thickness)/cross-sectional area. Before measurement, the instrument was calibrated with an open circuit and closed circuit using standard methods to reduce errors, and the experiments were repeated to check repeatability on the values, with the average error of ± 0.05.
3 Results and discussion
3.1 FT Raman studies
a–f FT Raman spectra of different concentrations of ZrO2-filled PVA/NaClO4 composites
Possible interaction of ZrO2-filled NaClO4/PVA polymer composites
3.2 Atomic force microscopic studies
AFM image of 3 wt% ZrO2-filled PVA/NaClO4 composites (a, b) and PVA/NaClO4 composites (c, d)
3.3 UV–visible studies
UV–visible transmittance spectra of different concentrations of ZrO2-filled PVA/NaClO4 composites
a UV–visible absorbance with wavelength and b ln(α) versus hν for different concentrations of ZrO2-filled PVA/NaClO4 composites
Optical parameters of ZrO2-filled PVA/NaClO4 films
Sample name | Absorption edge (nm) | E u (eV) | E g (direct) (eV) | E g (indirect) (eV) |
---|---|---|---|---|
0 wt% ZrO2 | 241 | 0.240 | 5.457 | 4.978 |
1 wt% ZrO2 | 245 | 0.432 | 5.197 | 4.777 |
2 wt% ZrO2 | 251 | 0.657 | 5.041 | 4.422 |
3 wt% ZrO2 | 262 | 0.754 | 4.936 | 4.132 |
4 wt% ZrO2 | 275 | 0.793 | 4.738 | 4.168 |
5 wt% ZrO2 | 283 | 0.870 | 4.642 | 4.268 |
Variation of a (αhν)1/2 versus hν and b E g indirect versus ZrO2 wt% of different concentrations of ZrO2-filled PVA/NaClO4 composites
The E g (direct) for the PVA/NaClO4 polymer matrix is 5.457 eV and it is decreased to 4.642 eV for 5 wt% ZrO2-filled PVA/NaClO4 polymer composite. The E g (indirect) for the PVA/NaClO4 polymer matrix is 4.978 eV and it is decreased to 4.132 eV for 3 wt% ZrO2-filled PVA/NaClO4 polymer composite and increased to 4.268 eV for 5 wt% ZrO2-filled PVA/NaClO4 polymer composite. In both the cases, the E g is maximum for PVA/NaClO4 matrix and decreases with increase in ZrO2 wt%, which indicates the formation of additional energy levels (defects). These additional energy levels produce localized states in the optical band gap that increases with increasing concentration of the defects. And also, the addition of ZrO2 forms the crystallites by local cross-linking within the amorphous phase of the polymer, leading to enhancement in crystallinity. This clearly indicates the changes in electronic structure and microstructure of the polymer due to the addition of ZrO2. But in case of indirect transition, the 3 wt% ZrO2-filled composite has shown minimum Eg and later it increased but not more than the PVA/NaClO4 polymer matrix.
3.4 Thermal analysis
TGA thermograms of different concentrations of ZrO2-filled PVA/NaClO4 composites
Thermal degradation steps and char content
Degradation | Step I | Step II | Step III | Step IV | Char content [%] ± 01 | ||||
---|---|---|---|---|---|---|---|---|---|
Sample name | T p —1 | % weight loss | T p —2 | % weight loss | T p —3 | % weight loss | T p —4 | % weight loss | |
PVA/NaClO4(P/N) | 65.62 | 12.89 | 297.81 | 38.78 | 439.78 | 16.54 | 549.00 | 23.06 | 8.13 |
P/N + 1%ZrO2 | 86.36 | 10.00 | 283.12 | 40.84 | 430.84 | 12.89 | 537.66 | 20.29 | 8.29 |
P/N + 2%ZrO2 | 91.89 | 08.75 | 280.68 | 37.44 | 439.02 | 11.83 | 541.29 | 21.46 | 10.58 |
P/N + 3%ZrO2 | 91.44 | 09.81 | 275.23 | 36.82 | 429.62 | 15.26 | 536.59 | 17.83 | 11.59 |
P/N + 4%ZrO2 | 93.53 | 10.30 | 280.83 | 38.32 | 425.38 | 16.88 | 526.97 | 20.13 | 12.16 |
P/N + 5%ZrO2 | 94.77 | 12.46 | 297.58 | 39.85 | 436.21 | 14.63 | 538.56 | 17.57 | 13.54 |
The second transitional region covers a wider temperature range 210 to 360 °C (step II). It includes melting point, physical transition, and the degradation temperature. The total weight loss of 36 to 41% occurred. The higher value of weight loss indicates the existence of a chemical degradation process. This degradation process occurs due to partial dehydration and the formation of polyene. The third degradation process occurs in the range 380 to 400 °C (step III). This degradation occurs due to intermolecular cyclization and condensation, i.e., scission of C–C bonds in polymeric backbone. Which means polyene decomposes into low-mass oxygen-containing products. During this carbonation process, 16% weight loss occurs. The fourth transition region at 490 to 600 °C (step IV) suggests that there may be a lack of saturation of end groups related to the combination and termination process (complex formation) between PVA and NaClO4 which leads to random scission in this temperature range. It leads to thermo-oxidation of carbonized residue [50, 51, 52].
DTA thermograms of different concentrations of ZrO2-filled PVA/NaClO4 composites
Kinetic parameters
Sample name | Ea (kJ/mol) | ΔH (kJ/mol) | ln A | ΔS (kJ/mol K) | ΔG (kJ/mol) | Onset temp. oC ± 05 |
---|---|---|---|---|---|---|
PVA/NaClO4(P/N) | 48.0 | − 2.4745 | 0.00148 | − 67.4077 | 17.5999 | 237 |
P/N + 1%ZrO2 | 47.5 | − 2.3523 | 0.00192 | − 67.2137 | 16.6769 | 232 |
P/N + 2%ZrO2 | 80.4 | − 2.3324 | 0.00107 | − 67.0755 | 16.4944 | 223 |
P/N + 3%ZrO2 | 123.1 | − 2.2870 | 0.00042 | − 67.0117 | 16.1566 | 220 |
P/N + 4%ZrO2 | 56.5 | − 2.3334 | 0.00106 | − 67.0801 | 16.5045 | 220 |
P/N + 5%ZrO2 | 36.7 | − 2.4729 | 0.00179 | − 67.3090 | 17.5570 | 217 |
Plots of Ln(Ln(1/Y)) versus (1/T) × 103 in decomposition range 200 to 400 °C
The negative value of ΔS suggests that the activated state of polymer complex is rigid and lower values of ΔS reveal that interaction between ZrO2 and PVA/NaClO4 is very less; too long time is required to form ZrO2/PVA/NaClO4 complex. It clearly suggests that ZrO2 particles were well dispersed in the PVA/NaClO4 polymer matrix [42]. The ΔG and ΔS collectively reveal that fillers are immiscible in the polymer matrix.
3.5 Conductivity studies
Current–voltage graph of different concentrations of ZrO2-filled PVA/NaClO4 composites
Variation of conductivity versus ZrO2 wt% for different concentrations of ZrO2-filled PVA/NaClO4 composites
ZrO2 fills the gap between adjacent conducting phases and forms an insulating phase between them. At lower percentage, ZrO2 is wrapped by conductive polymer matrix so it will support conductivity. Further increase in ZrO2 fillers beyond 3 wt% increases the density of the insulating phase. These insulating fillers form clusters of insulating phases. These phases oppose the ionic movement or polymer chain segmental motion as a mere insulator. Hence, conductivity decreases [54, 55]. Gustav et al. reported that PVA mixed with lithium bis(triflouromethane) sulfonamide salt shows conductivity of about 10−4 Scm−1 at 60 °C [56]. F. Kingslin Mary Genova et al. prepared electrolytes based on lithium triflate-doped PVA-PAN polymer electrolyte and reported conductivity of about 10−5 Scm−1 [57]. YF Huang et al. prepared polyethylene glycol-borate ester/lithium fluoride in graphene oxide/poly(vinyl alcohol)-based electrolyte membrane with a conductivity of about 10−4 Scm−1 and predicted that such electrolytes are promising candidates for a new battery separator [58]. Looking at the literature, in case of 3 wt%, ZrO2 film shows conductivity around 10−4 Scm−1; therefore, the prepared composite films will be a promising candidate for a battery separator in sodium-based battery applications.
4 Conclusion
The freestanding films of PVA and NaClO4 polymer nanocomposites with different concentrations of ZrO2 were prepared using the solution casting method. FT Raman studies confirmed the interaction between PVA and NaClO4 and well-dispersed ZrO2 particles within a polymer matrix. The AFM image of nanofilled film shows lumps which occurred due to the nanofiller association with the polymer matrix. The thermal stability of the composites was observed around 230 °C. Broid’s method was used to calculate thermodynamic parameters. Thermal kinetic parameters also support the results obtained from FT Raman studies. Optical energy band gap and conductivity values are in correlation with each other. Increase in conductivity is attributed to the formation of less ordered region and decrease in conductivity at higher wt% is attributed to the aggregation of the insulating phase in between conducting sites. Three weight percent ZrO2-filled PVA/NaClO4 composite has shown good properties that can be used as a polymer electrolyte.
Notes
Acknowledgements
The authors are thankful to USIC, Karnatak University, Dharwad, for FT Raman, TGA, and AFM facilities.
Compliance with ethical standards
Conflict of interest
The authors declare that they have no conflicts of interest.
References
- 1.Jancar J, Douglas JF, Starr FW, Kumar SK, Cassagnau P, Lesser AJ, Sternstein SS, Buehler MJ (2010) Current issues in research on structure property relationships in polymer nanocomposites. Polymer 51:3321–3343CrossRefGoogle Scholar
- 2.Yang R, Ogitani S, Paul K, Wong CP (2002) Novel polymer–ceramic nanocomposite based on high dielectric constant epoxy formula for embedded capacitor application. J Appl Polym Sci 83:1084–1090CrossRefGoogle Scholar
- 3.Huanan W, Yubao L, Zuo Y, Jihua L, Sansi M, Cheng L (2007) Biocompatibility and osteogenesis of biomimetic nano-hydroxyapatite/polyamide composite scaffolds for bone tissue engineering. Biomaterials 28:3338–3348CrossRefGoogle Scholar
- 4.Vallerie HD, Thanh DN, Mangesh N, Nandika AD, Teresa DG (2012) Polymer nanocomposites for improved drug delivery efficiency. Mater Chem Phys 132:409–415CrossRefGoogle Scholar
- 5.Sheng-Wen Z, Shu-Xue Z, Yu-Ming W, Li-Min W (2005) Synthesis of SiO2/polystyrene nanocomposite particles via miniemulsion polymerization. Langmuir 21:2124–2128CrossRefGoogle Scholar
- 6.Steven H (2014) Fuel cell catalyst layers: a polymer science perspective. Chem Mater 26:381–393CrossRefGoogle Scholar
- 7.Jinyao C, Cindy XZ, Matthew MZ, Wang K, Deng L, Xu G (2012) Alkaline direct oxidation glucose fuel cell system using silver/nickel foams as electrodes. Electrochim Acta 66:133–138CrossRefGoogle Scholar
- 8.Adam JG, Rona C, Andrew JC, Colleen L, Coline J, Arbel AS, Daniel A, Irene Y, Molly MS (2015) Layer-by-layer self-assembly of polymer films and capsules through coiled-coil peptides. Chem Mater 27:5820−5824Google Scholar
- 9.Zheng-Ming H, Zhang YZ, Kotaki M, Ramakrishna S (2003) A review on polymer nano-fibers by electro-spinning and their applications in nano-composites. Compos Sci Technol 63:2223–2253CrossRefGoogle Scholar
- 10.Feng H, Yugang S, Anshu G, Matthew AM, Lise B, Lolita R, Jingfeng W, Phil G, Moonsub S, John AR (2004) Polymer imprint lithography with molecular-scale resolution. Nano Lett 4(12)Google Scholar
- 11.Long Y, Katherine D, Lin L (2006) Polymer blends and composites from renewable resources. Prog Polym Sci 31:576–602CrossRefGoogle Scholar
- 12.Lucy LD, Cindy XZ, Yiqun M, Sean SC, Xu G (2013) Low cost acetone sensors with selectivity over water vapor based on screen printed TiO2 nanoparticles. Anal Methods 5:3709CrossRefGoogle Scholar
- 13.Kevin KW, Han Y, Cindy XZ, Xu G, Yu Q, Wu Y, Hu N-X (2010) Direct method of tracing the wetting states on nanocomposite surfaces. Langmuir 26(11):7686–7689CrossRefGoogle Scholar
- 14.Cindy XZ, Steven X, Gu X (2015) Density of organic thin films in organic photovoltaics. J Appl Phys 118:044510CrossRefGoogle Scholar
- 15.Paul DR, Robeson LM (2008) Polymer nanotechnology: nanocomposites. Polymer 49:3187–3204CrossRefGoogle Scholar
- 16.Wang H, Xu P, Zhong W, Liang S, Qiangguo D (2005) Transparent poly(methyl methacrylate)/silica/zirconia nanocomposites with excellent thermal stabilities. Polym Degrad Stab 87:319–327CrossRefGoogle Scholar
- 17.Young MK, Chang JB, Su-Hee L, Hae-W K, Hyoun EK (2005) Improvement in biocompatibility of ZrO2–Al2O3 nanocomposite by addition of HA. Biomaterials 26:509–517CrossRefGoogle Scholar
- 18.Xue B, Andrea P, Vania TF, Rute ASF, Nicola P (2012) One-step synthesis and optical properties of benzoate- and biphenolate-capped ZrO2 nanoparticles. Adv Funct Mater 22:4275–4283CrossRefGoogle Scholar
- 19.Cao HQ, Qiu XQ, Luo B, Liang Y, Zhang YH, Tan RQ, Zhao MJ, Zhu QM (2004) Synthesis and room-temperature ultraviolet photoluminescence properties of zirconia nanowires. Adv Funct Mater 3:243–246CrossRefGoogle Scholar
- 20.Junkai Z, Shengsong G, Lirong L, Qian S, Xianmin M, Cindy XZ, Luhan H, Tingting W, Zepei Y, Zhanhu G (2018) Microwave solvothermal fabrication of zirconia hollow microspheres with different morphologies using pollen templates and their dye adsorption removal. Ind Eng Chem Res 57(1):231–241CrossRefGoogle Scholar
- 21.Jose FB, Anton S, Heinz-D K, Janet G, Frank AM (2016) New ZrO2/Al2O3 nanocomposite fabricated from hybrid nanoparticles prepared by CO2 laser Co-vaporization. Sci Rep 6:20589CrossRefGoogle Scholar
- 22.Sangkyu L, Hyeon-Jin S, Seon-Mi Y, Dong Kee Y, Jae-Young C, Ungyu P (2008) Refractive index engineering of transparent ZrO2–poly dimethyl siloxane nanocomposites. J Mater Chem 18:1751–1755CrossRefGoogle Scholar
- 23.Nikhil HJ, Katherine D, Ravindra D (2005) Synthesis and characterization of Nafion® - MO2 (M = Zr, Si, Ti) nanocomposite membranes for higher temperature PEM fuel cells. Electrochim Acta 51:553–560CrossRefGoogle Scholar
- 24.Basudam A, Sarmishtha M (2004) Polymers in sensor applications. Prog Polym Sci 29:699–766CrossRefGoogle Scholar
- 25.Martin Z, Anja H, Alex F, Helmut S, Christian S, Georg J, Gunther L, Barbara S, Ingrid G, Norbert G, Reinhard S, Simona BG, Siegfried B (2007) Low-voltage organic thin-film transistors with high-k nanocomposite gate dielectrics for flexible electronics and optothermal sensors. Adv Mater 19:2241–2245CrossRefGoogle Scholar
- 26.Shadpour M, Ahmadreza NE (2015) A simple and environmentally friendly method for surface modification of ZrO2 nanoparticles by biosafe citric acid as well as ascorbic acid (vitamin C) and its application for the preparation of poly(vinyl chloride) nanocomposite films. Polym Compos. https://doi.org/10.1002/pc.23746
- 27.Xiaodong W, Xianhu L, Hongyue Y, Hu L, Chuntai L, Tingxi L, Chao Y, Xingru Y, Changyu S, Zhanhu G (2018) Non-covalently functionalized graphene strengthened poly(vinyl alcohol). Mater Des 139:372–379CrossRefGoogle Scholar
- 28.Saligheh O, Khajavi R, Yazdanshenas ME, Rashidi A (2015) Fabrication and optimization of poly(vinyl alcohol)/zirconium acetate electrospun nanofibers using Taguchi experimental design. J Macromol Sci Phys 54:1391–1403CrossRefGoogle Scholar
- 29.Jagadish N, Bhajantri RF (2018) Physical and electrochemical studies on ceria filled PVA proton conducting polymer electrolyte for energy storage applications. J Inorg Organomet Polym Mater. https://doi.org/10.1007/s10904-018-0801-3.
- 30.Wei D, Suying W, Jiahua Z, Xuelong C, Dan R, Zhanhu G (2010) Manipulated electrospun PVA nanofibers with inexpensive salts. Macromol Mater Eng 295:958–965CrossRefGoogle Scholar
- 31.Arumugam M, Xingwen Y, Shaofei W (2017) Lithium battery chemistries enabled by solid-state electrolytes. Nat Rev Mater 2(16103):1–16Google Scholar
- 32.Clement B, Xiulei J (2018) Electrolytes, SEI formation, and binders: a review of nonelectrode factors for sodium ion battery anode. Small 1703576:1–20Google Scholar
- 33.Mohammed IJ, Prakash AS (2018) Advancement of technology towards developing Na-ion batteries. J Power Sources 378:268–300CrossRefGoogle Scholar
- 34.Premkumar S, Gwenaelle R, Vincent S, Tarascon JM, Palacin MR (2011) Na2Ti3O7: lowest voltage ever reported oxide insertion electrode for sodium ion batteries. Chem Mater 23:4109–4111CrossRefGoogle Scholar
- 35.Bhargav PB, Mohan VM, Sharma AK, Rao VVRN (2007) Structural, electrical and optical characterization of pure and doped poly (vinyl alcohol) (PVA) polymer electrolyte films. Int J Polym Mater 56:579–591CrossRefGoogle Scholar
- 36.Alexandre P, Elena M, Matthieu C, Jean MT, Palacin MR (2012) In search of an optimized electrolyte for Na-ion batteries. Energy Environ Sci 5:8572CrossRefGoogle Scholar
- 37.Ponrouch A, Monti D, Boschin A, Steen B, Johansson P, Palacin MR (2015) Non-aqueous electrolytes for sodium-ion batteries. J Mater Chem A 3:22–42CrossRefGoogle Scholar
- 38.Amrtha B, Jonas H, Anna KD, Jurgen J, Philipp A (2014) Electrochemical stability of non-aqueous electrolytes for sodium-ion batteries and their compatibility with Na0.7 CoO2. Phys Chem Chem Phys 16:1987CrossRefGoogle Scholar
- 39.Hebbar V, Bhajantri RF, Naik J (2017) Physico-chemical properties of bismuth nitrate filled PVA-LiClO4 composites for energy storage applications. J Mater Sci Mater Electron 28:5827–5839CrossRefGoogle Scholar
- 40.Naik J, Bhajantri RF, Sheela T, Rathod SG (2016) Role of ZrO2 on physico-chemical properties of PVA/NaClO4 composites for energy storage applications. Polym Compos. https://doi.org/10.1002/pc.24063
- 41.Moses E, Andre W, Ellen IT (2013) A novel method for measuring the effective conductivity and the contact resistance of porous electrodes for lithium-ion batteries. Electrochem Commun 34:130–133CrossRefGoogle Scholar
- 42.Schantz S (1991) On the ion association at low salt concentrations in polymer electrolytes; a Raman study of NaCF3SO3 and LiClO4 dissolved in poly (propylene oxide). J Chem Phys 94:6296CrossRefGoogle Scholar
- 43.Pitchai JV, Bijan D, Dilip KH (2001) A study on the solvation phenomena of some sodium salts in 1,2-dimethoxyethane from conductance, viscosity, ultrasonic velocity, and FT-Raman spectral measurements. J Phys Chem A 105(24):5960–5964CrossRefGoogle Scholar
- 44.Jayakumar S, Ananthapadmanabhan PV, Perumal K, Thiyagarajan TK, Mishra SC, Su LT, Tok AIY, Guo J (2011) Characterization of nano-crystalline ZrO2 synthesized via reactive plasma processing. Mater Sci Eng B 176:894–899CrossRefGoogle Scholar
- 45.Gunasekaran S, Sailatha E, Seshadri S, Kumaresan S (2009) FTIR, FT Raman spectra and molecular structural confirmation of ionized. Indian J Pure Appl Phys 47:12–18Google Scholar
- 46.Sareen S, Nagaraja GK, Jagadish N, Bhajanthri RF (2017) Development and characterization study of silk fibre reinforced poly(vinyl alcohol) composites. Int J Plast Technol 21(1):108–122CrossRefGoogle Scholar
- 47.Shadpour M, Leila M (2014) Improvement of the interactions between modified ZrO2 and poly(amide-imide) matrix by using unique biosafe diacid as a monomer and coupling agent. Polym-Plast Technol Eng 53:1574–1582CrossRefGoogle Scholar
- 48.Xi Z, Xingru Y, Qingliang H, Huige W, Jun L, Jiang G, Hongbo G, Jingfang Y, Jingjing L, Daowei D, Luyi S, Suying W, Zhanhu G (2015) Electrically conductive polypropylene nanocomposites with negative permittivity at low carbon nanotube loading levels. ACS Appl Mater Interfaces 7:6125–6138CrossRefGoogle Scholar
- 49.Vidyashree H, Bhajantri RF, Jagadish N, Sunil GR (2016) Thiazole yellow G dyed PVA films for optoelectronics: microstructrural, thermal and photophysical studies. Mater Res Express 3:075301CrossRefGoogle Scholar
- 50.Liew CW, Ramesh S, Arof AK (2015) Characterization of ionic liquid added poly(vinyl alcohol)-based proton conducting polymer electrolytes and electrochemical studies on the super capacitors. Int J Hydrogen Energy 40:852–862CrossRefGoogle Scholar
- 51.Bo J, Juan S, Rufang P, Yuanjie S, Bisheng T, Shijin C, Haishan D (2012) Synthesis, characterization, thermal stability and sensitivity properties of the new energetic polymer through the azidoacetylation of poly(vinyl alcohol). Polym Degrad Stab 97:473–480CrossRefGoogle Scholar
- 52.Haigang Y, Shoubin X, Yuanqing S, Jianling Z, Long J, Yi D (2014) Study of the thermal decomposition behavior of poly(vinyl alcohol) with NaHSO4. J Macromol Sci B 53:1059–1073CrossRefGoogle Scholar
- 53.Broido A (1969) A simple, sensitive graphical method of treating thermo-gravimetric analysis data. J Polym Sci A-2 7:1761–1773CrossRefGoogle Scholar
- 54.Karthika JS, Vishalakshi B, Naik J (2016) Gellan gum graft polyaniline, an electrical conducting biopolymer. Int J Biol Macromol 82:61–67CrossRefGoogle Scholar
- 55.Rajendran S, Uma T (2000) Effect of ceramic oxide on PVC-PMMA hybrid polymer electrolytes. Ionics 6:288–293CrossRefGoogle Scholar
- 56.Gustav EK, Daniel B (2017) Li-ion batteries using electrolyte based on mixtures of poly(vinyl alcohol) and lithium bis(trifluoro methane) sulfonamide salt. Electrochemica acta 246:208–212CrossRefGoogle Scholar
- 57.Genova FKM, Selvasekarpandian S, Vijaya N, Sivadevi S, Premalatha M, Karthikeyan S (2017) Lithium ion conducting polymer electrolyte based on PVA-PAN doped with lithium triflate. Ionics 23(10):2727–2734CrossRefGoogle Scholar
- 58.Haung YF, Zhang MQ, Rong MZ, Ruan WH (2017) To immobilize poly ethylene glycol-borate/lithium fluoride in graphene oxide/polyvinyl alcohol for synthesizing new polymer electrolyte membrane of lithium ion batteries. Express Polym Lett 11(1):35–46CrossRefGoogle Scholar