Investigation of structural and conductivity properties of poly(vinyl alcohol)-based electrospun composite polymer blend electrolyte membranes for battery applications

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In the present study, we have made an attempt to prepare complexed PVA-PVP-KNO3-BaTiO3 blend composite polymer electrolyte membranes composed of potassium nitrate (KNO3) as salt and BaTiO3 of various concentrations as filler and studied their properties. The advantages of addition the fillers are the increase in ionic conductivity at room temperatures and the improvement of the stability at the interface with electrodes.

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Nội dung Text: Investigation of structural and conductivity properties of poly(vinyl alcohol)-based electrospun composite polymer blend electrolyte membranes for battery applications

Cite this paper: Vietnam J. Chem., 2023, 61(2), 158-169 Research article DOI: 10.1002/vjch.202100050 Investigation of structural and conductivity properties of poly(vinyl alcohol)-based electrospun composite polymer blend electrolyte membranes for battery applications Rahmat Gul*, Wan Ahmad Kamil Mahmood School of Chemical Sciences, University Sains Malaysia, 11800 Minden, Pulau Penang, Malaysia Submitted May 24, 2021; Revised June 17, 2022; Accepted October 4, 2022 Abstract Solid polymer electrolyte has attracted great interest for the next generation of electrochemical devices such as batteries, but the low ionic conductivity and poor stability has retarded their commercial acceptance for energy storage devices applications. To overcome these issues, strategies to develop composite polymer electrolytes (CPEs) are drawing interest. Nanocomposite solid polymer blend electrolyte membranes based on poly (vinyl alcohol) (PVA), poly (vinyl pyrrolidone) (PVP) of various compositions that contained potassium nitrate (KNO 3) as a dopant salt, and Barium Titanate (BaTiO3) as a filler were prepared with various concentrations of filler using electrospinning technique. The structural and complex formations due to interaction of various groups of the prepared composite polymer electrolyte membranes were investigated using X-ray diffraction (XRD) and Fourier transform infra-red (FTIR) spectral analysis. The conductivity of the PVA-PVP-KNO3-BaTiO3 polymer electrolyte systems was found to vary between 3.7110-9 and 1.9910-5 S cm-1 at 298 K with the increase in filler concentration. The maximum room temperature ionic conductivity (1.9910-5 S cm-1) has been obtained for 9 wt% BaTiO3 doped polymer electrolyte system. The addition of filler also enhanced the thermal stability of the electrolyte. The temperature dependence ionic conductivity of the prepared complexed polymer electrolyte systems appears to obey Arrhenius behaviour. Keywords. Composite polymer electrolyte, ionic conductivity, nanofiber membrane, electrospinning, inorganic filler. 1. INTRODUCTION temperature and remain chemically unreactive. The addition of inert metal oxide filler that may act as Development of new solid polymer electrolyte system solid plasticizers generally improves the transport has been an important area of research which properties of polymer electrolytes and interfacial attracted attention for more than three decades, to find stability of the electrode-electrolyte interface. Such new types of electrolyte for fundamental knowledge enhancement in conductivity can be explained by and for their potential practical applications in various decrease in degree of crystallinity of the polymer solid state electrochemical devices.[1-8] Recently matrix.[13] The increase in ionic conductivity of extensive investigations on such solid polymer composite solid electrolytes by incorporation of metal electrolytes (SPE) have been in progress. Various oxide fillers associated with concentration and advantages are realized by using a thin membrane of particle size of the inert filler. The enhancement in solid polymer electrolytes in place of a conventional ionic conductivity may be due to the development of liquid electrolyte in electrochemical devices. Polymer a new kinetic path through a thin interface layer.[14-20] electrolyte materials exhibits high ionic conductivity, Polymer electrolytes were prepared with various good mechanical properties, ease of fabrication, metal oxides as fillers such as Al2O3, TiO2, ZrO2, compatibility with electrode material, and wide SiO2, and BaTiO3 which display high ionic electrochemical stability. Addition of small size conductivity values with good mechanical and inorganic metal oxide additives in polymer electrolyte thermal stability at room temperature. The addition systems is used to improve the morphological, of a small amount of inert filler causes remarkable mechanical and electrochemical properties of ionic conductivity in the composite complexed polymer electrolytes.[9-12] Inorganic metal oxide polymer electrolyte systems. Therefore size and materials are mostly stable up to very high concentration of the filler particles play an important 158 Wiley Online Library © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Rahmat Gul et al. role in the polymer electrolytes.[21] composite polymer electrolytes have been measured Researchers have used various host polymers, and an improvement of ionic conductivity by such as poly (vinyl chloride) (PVC), poly (vinyl addition of BaTiO3 into composite polymer alcohol) (PVA), poly (ethylene oxide) (PEO), poly electrolyte based on PVA-PVP-KNO3-BaTiO3 is (vinyl pyrrolidone) (PVP), poly (methyl reported. XRD analysis has been carried out to methacrylate) to improve the ionic conductivity and investigate the structural features of the prepared thermomechanical stability for their practical nanocomposite polymer blend electrolyte applications as polymer electrolytes in various membranes. Interactions among various components electrochemical devices.[22-25] Poly (ethylene oxide) have been studied by FTIR analysis. (PEO) is an attractive polymer for development of materials used for electrochemical devices 2. MATERIALS AND METHODS applications but ionic conductivity of these materials is very low at room temperature due to semi- 2.1. Materials crystalline nature of PEO. Therefore practical applications of PEO based materials are limited. Poly(vinyl alcohol) (PVA) with an average Many researchers have worked on these polymer molecular weight of 5×105 (Aldrich, USA), electrolyte materials. However, no work has been poly(vinyl pyrrolidone) (PVP) with an average reported on blended PVA-PVP with BaTiO3 as filler. molecular weight of 10×105 (Aldrich, USA), Hence we used poly (vinyl alcohol) (PVA)-poly inorganic salt potassium nitrate (KNO3) (E-Merck, (vinyl pyrrolidone) (PVP) blend based polymer Germany), and BaTiO3 with particle sizes of 100 nm electrolyte because PVA is a polymer with (Sakai Chemical Industries, Japan) were used remarkable dielectric strength, and excellent charge without any further purification in the present study. storage capacity. It has hydroxyl (OH) groups All the reagents used to prepare polymer electrolyte attached to methane carbon of its carbon chain complex membranes were analytical grade. PVA, backbone which assist the formation of complexed PVP, KNO3 and BaTiO3 were vacuum dried before polymer electrolyte systems due to hydrogen use, in the oven at 60 °C, for 24 hours to remove bonding. Another interesting feature of PVA is the moisture and other volatile impurities. All other possibility to directly functionalize the methoxy reagents were commercially available and used as groups with cations, thus obtaining a single ion received for preparation of polymer electrolyte conductor. Poly (vinyl pyrrolidone) (PVP) is an membranes in the electrospinning experiments. amorphous polymer and display good environmental stability. PVP has been found to be inert, nontoxic 2.2. Preparation of samples polymer with good charge storage capacity and optical properties. PVP shows a tendency for Poly(vinyl alcohol) (PVA), poly(vinyl pyrrolidone) complexation with salts and metal oxide fillers.[26] (PVP) and BaTiO3 filler were used as the starting In the present study, we have made an attempt to materials for the preparation of fibrous prepare complexed PVA-PVP-KNO3-BaTiO3 blend nanocomposite polymer electrolyte membranes by composite polymer electrolyte membranes electrospinning technique. All the starting materials composed of potassium nitrate (KNO3) as salt and were dried at 50 °C for 48 hours in hot air oven BaTiO3 of various concentrations as filler and before use. Polymer solutions for electrospinning studied their properties. The advantages of addition were prepared from 16 wt% poly(vinyl alcohol) the fillers are the increase in ionic conductivity at (PVA). For the development of fibrous room temperatures and the improvement of the nanocomposite polymer electrolyte membranes, 16 stability at the interface with electrodes. The wt% of PVA and PVP polymer solutions were composite polymer electrolyte systems in the past prepared by dissolving the required amounts of PVA were mainly based on alkali metal salt, especially and PVP in triple distilled water homogeneously lithium salt. There have been studies on solid under continuous magnetic stirring for 6 hours at polymer electrolytes with sodium and potassium room temperature to obtain a homogeneous viscous salts. Compared to lithium, potassium is soft, low solution and degassed to remove air bubbles. Later, cost, easily available and good contact with various 3, 6, 9, 12, 15 wt% of BaTiO3 nanoparticle filler and components of the electrochemical devices. The 10 wt% KNO3 were added to the above optimized resulting polymer electrolyte materials were 16 wt% polymer solution under constant stirring of characterized for their crystalline structure, ionic the ingredients for 6 hours to obtain homogeneous conductivity, thermal stability and the results are and transparent polymer solutions containing discussed in detail. Ionic conductivities of the BaTiO3 of concentration varying in the range of 3-15 © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 159
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Investigation of structural and conductivity properties… wt% and then cooled to room temperature. The temperature using an X-ray diffractometer (XRD resulting polymer solution was degassed to remove Bruker D-8 Advance). The thermal stability of the air bubbles. The resultant viscous polymer solutions polymer electrolyte films in terms of the % weight were electrospun to prepare the membranes. The loss were characterized by thermogravimetric polymer solution was held in a 3 ml syringe and analysis (TGA) using a PerkinElmer (pyres loaded in a syringe withdrawal pump (New Era diamond) instrument at a heating rate of 10 °C min-1 Pump Systems Inc., model NE-300) to prepare from room temperature to 500 °C. The TGA electrospun nanocomposite fiber polymer electrolyte measurements were done under nitrogen atmosphere membranes by electrospinning technique after with a gas flow of 50 ml min-1. setting the essential electrospinning parameters. The electrospinning was carried out at room temperature; 3. RESULTS AND DISCUSSION a high applied voltage of 20 kV between spinneret and collector was applied by using a high voltage 3.1. Conductivity studies power supply (Spellman, model CZE1000R) which could generate positive DC voltages up to 30 kV, Various polymer electrolytes were subjected to ionic and distance between the tip of the spinneret and conductivity measurement at different temperatures, collector was 10 cm, needle bore size 24 G, the in order to find out the influence of temperature on solution flow rate was 2 ml h-1, and the filler ionic conductivity of these electrolytes. Figure 1 concentrations in the blend polymer solution were 3, shows the temperature dependence of ionic 6, 9, 12, and 15 wt%. The electrospun fibrous conductivity plots of PVA-PVP-KNO3-BaTiO3 nanocomposite polymer electrolyte membranes were based composite polymer blend electrolyte systems collected on a grounded stainless steel plate covered with 3, 6, 9, 12 and 15 wt% BaTiO3 as filler with a thin aluminum foil and dried under vacuum in concentration. All these different systems contain a oven at 50°C for 48 hours to remove the solvent fixed content of polymers, and salt with various before further use. All experiments were carried out contents of BaTiO3 as filler. It shows the Arrhenius at room temperature and below 25% environmental plots of nanocomposite polymer blend electrolyte humidity. After electrospinning, each of the obtained systems in the temperature range 298-353 K. Over nanofiber membranes was carefully peeled off from the temperature range studied, the PVA-PVP-KNO3- the stainless steel plate and stored in a glove box. BaTiO3 with 9 wt% BaTiO3 composite polymer blend electrolyte has the highest conductivity. It can 2.3. Characterization also be observed from conductivity-temperature plots, that all of these samples follow an Arrhenius Conductivity measurements of the prepared samples relation. In this figure, any abrupt variation in ionic of the polymer electrolyte systems were carried out conductivity with temperature is not observed in the at various temperatures. A measurement of ionic temperature range studied. The smooth variation of conductivity of the samples was performed by conductivity with temperature indicates that all sandwiching the given polymer electrolyte samples exhibit a completely amorphous membrane samples between two polished stainless structure.[27] Figure 1 shows that ionic conductivity steel disk electrodes, with diameter of 1 cm, which versus temperature behavior of the polymer blend acted as blocking electrodes for ions. The stainless system is linear, i.e. follows Arrhenius relationship steel electrodes, with samples, were sealed in an air which indicates that there is no phase transition tight glass container and mounted onto fixed holder. occurs in the polymer matrix of the systems. This The film samples were cut into small pieces of means that the possible mechanism of ionic shaped disc, with diameters of about 20 mm. The conductivity is jumping of ions from one site to thin film samples were inspected visually before another and the nature of cation transport in all measurement and found free from pores. The study samples seems to be similar to that in ionic was performed in the scanning frequency range of 1 crystals.[28-29] The ionic conductivity (σ) values mHz to 100 KHz, using high frequency analyzer varies with temperature (T) according to the LCR Hi tester analyzer, Model Hioki 3522-50, equation Japan. The temperature dependent ionic conductivity σ = σ0exp (-Ea/kT) of the prepared polymer electrolyte samples was where σ0 is pre-exponential factor, Ea is activation carried out at five different temperatures, in the energy, k is Boltzman constant, and T is absolute temperature range of 298-353 K viz. 298, 313, 323, temperature. 333, 343 and 353 K. The polymer electrolyte From figure 1, it can be observed that as samples were subjected to phase analysis at room temperature increases the ionic conductivity values © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 160
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Rahmat Gul et al. of the composite polymer blend electrolyte systems conductivity. The increase in conductivity with also increases in all different compositions. The temperature can be associated with the increase in behavior of ionic conductivity enhancement with polymeric chain flexibility due to a decrease in temperature for all the complexes is in agreement viscosity.[32] The polymer chains expand with raise with the free volume model and can be understood in temperature which leads to produce free volume. in terms of the theory.[30] The enhancement in Thus, free volume increases with temperature in conductivity with temperature may be due to the polymer electrolyte systems. The resulting reason that at low temperature, ionic mobility (K+) conductivity, represented by the mobility of ions and and polymeric segmental motions are restricted, polymer chains, can be determined by the available because of strong polymer salt association. At higher free volume around the polymer chains in the temperatures, conductivity increases due to the matrix. Thus, ions, solvated molecules, or polymer decrease in polymer salt association and increased segments move into the available free volume with thermal polymeric segmental motion of chains in the raise in temperature.[33] The development of free composite polymer electrolyte systems having a volume leads to enhance the ionic and polymer completely amorphous nature, which leads to an segmental mobility that will enhance ionic increase in the free volume, thereby support ionic conductivity and compensate for the retarding effect conduction via polymeric electrolyte system.[31] The of the ionic clouds. temperature can activate different percolation Temperature dependent ionic conductivity (K+) pathways for the charge migration. In addition, the values of PVA-PVP-KNO3-BaTiO3 composite temperature can modulate the segmental and local polymer electrolytes have been determined and are motions of the polymer backbone and listed in table 1 over the temperature range of 298- functionalities, thus enabling the resulting ionic 353 K. -1 Pure PVA -2 3 wt% 6 wt% 9 wt% -3 12 wt% 15 wt% -4 Log σ (S cm-1) -5 -6 -7 -8 -9 -10 2.8 2.9 3 3.1 3.2 3.3 3.4 1000/T (K-1) Figure 1: Arrhenius plot of log conductivity against reciprocal temperature of PVA-PVP-KNO3-BaTiO3 polymer complexes with different BaTiO3 concentrations The influence of the BaTiO3 concentration on when the weight percentage of BaTiO3 is 9 wt%. the K+ ion conductivity of PVA-PVP-KNO3-BaTiO3 The maximum ionic conductivity value of 1.99×10-5 composite polymer blend electrolyte systems studied S cm-1 was found at room temperature for the PVA- at various temperatures ranging from 298-353 K is PVP-KNO3-BaTiO3 (60-30-10-9) composite shown in figure 2. From the plot it is noted that polymer blend electrolyte system. While, the initially, the ionic conductivity of the electrolyte conductivity shows a decrease beyond saturation medium increases with the increase of nano filler level of concentration, with further addition of the content in the polymer matrix up to a certain amount BaTiO3 filler content at the range of temperature of filler concentration, and attain maximum value studied. The decrease in ionic conductivity, at higher © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 161
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Investigation of structural and conductivity properties… concentration of filler, may be due to dilution crystallinity of composite polymer electrolyte effect.[34-35] The ionic conductivity of the composite systems. The reduction in crystallinity at low polymer electrolyte systems remarkably increases by concentration may be due to the fact that the surface incorporation of ceramic fillers at a lower of the dispersed filler interacts with the polymer concentration into the polymer matrix. The addition chains and other electrolyte components in the of filler enhances free volume, which leads to higher polymer electrolyte. This allows transportation of salt dissociation. The dissociation of salt produce movable ions more freely either on the surface of the amorphous region because of specific interactions particles or through a polymer phase at the interface, occurring between various component materials. A which results in an appreciable increase in the polymer chain in the amorphous phase (less ordered conductivity.[39] A new transport mechanism regions) display more flexibility, which improve the develops due to an interaction of the polymer matrix polymeric segmental motion and local structural and filler which provides a conducting pathway for relaxation which causes remarkable enhancement in the transportation of ions. The increase in ionic the ionic conductivity of the composite polymer conductivity can be attributed to the metal oxide electrolyte films.[36-38] An increase of ionic fillers, acting as a nucleation centers for the conductivity with BaTiO3 content in the parent formation of crystallites in the composite polymer system may be attributed to a reduction of electrolyte systems. Table 1: Conductivity data of various PVA-PVP-KNO3-BaTiO3 polymer electrolytes at different temperatures Wt.% Conductivity (Scm-1) at various temperatures BaTiO3 298 K 303 K 313 K 323 K 333 K 343 K 348 K 353 K (wt.%) σ(S/cm) σ(S/cm) σ(S/cm) σ(S/cm) σ(S/cm) σ(S/cm) σ(S/cm) σ(S/cm 0 1.12E-09 2.00E-09 3.98E-09 6.03E-09 7.59E-09 1.00E-08 1.26E-08 2.00E-08 3 3.72E-09 1.15E-08 1.26E-07 1.70E-06 2.19E-05 2.63E-04 7.41E-04 1.51E-03 6 6.17E-08 1.91E-07 1.48E-06 1.23E-05 1.05E-04 7.76E-04 1.70E-03 3.16E-03 9 2.00E-05 4.79E-05 1.91E-04 7.59E-04 2.82E-03 9.12E-03 1.55E-02 2.45E-02 12 2.75E-06 6.31E-06 3.02E-05 1.66E-04 1.05E-03 5.37E-03 1.05E-02 1.74E-02 15 4.57E-07 9.77E-07 5.50E-06 3.72E-05 3.02E-04 2.19E-03 4.17E-03 6.31E-03 0 -1 -2 -3 -4 Log σ (S cm-1) -5 298 K -6 303 K -7 313 K 323 K -8 333 K 343 K -9 348 K 353 K -10 0 2 4 6 8 10 12 14 16 BaTiO3 (Wt%) Figure 2: Plot of log conductivity vs. composition of PVA-PVP-KNO3-BaTiO3 at various temperatures © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 162
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Rahmat Gul et al. The maximum ionic conductivity of PVA-PVP- films, up to 9 wt% weight percentage, thereby KNO3-BaTiO3 composite polymer electrolyte increasing the ionic conductivity values. The system containing 9 wt% BaTiO3 filler concentration polymer electrolyte system of the PVA-PVP-KNO3- is found to be 1.9910-5 S cm-1 at room temperature. BaTiO3 (60-30-10-9) composition is a kind of On the other hand, with any further raise in threshold in terms of filler concentration. However, concentration of the filler BaTiO3 above 9 wt%, the systems with a higher concentration of filler ionic conductivity decreases[40] because high beyond this ratio, which are obtained by further concentrations of inorganic fillers decreases the incorporation of BaTiO3 filler concentration, dipoles in the polymer matrix, and increases activation energy values increases and ionic coordination effect between the filler particles. Thus conductivity values decreases. The minimum value high content of filler leads to well defined crystallite of activation energy suggests that ionic conductivity regions due to aggregation of particles which tend to is highest in the composite polymer electrolyte impede ionic movement by acting as an insulator. system of optimum composition containing 9 wt% The activation energy (Ea) values for various BaTiO3 filler. The low values of activation energy systems of electrospun nanocomposite polymer for ionic transportation can be explained on the basis electrolyte membranes have been calculated by that presence of amorphous region of electrospun using the values of the slopes of log σ versus 1/T polymer electrolyte membranes provides free plots at common temperature from an Arrhenius volume which facilitates the ionic mobility in relation. Activation energy (Ea) and room polymer matrix. It can be noted that polymer temperature ionic conductivity values of various electrolyte membrane (PVA-PVP-KNO3-BaTiO3) compositions are summarized in table 2. It can be (60-30-10-9) has significantly low activation energy found from the table, that activation energy values (0.41 eV) for the ionic transportation and highest decreases with the increase in the concentration of ionic conductivity values when compared to other BaTiO3 filler in PVA-PVP blend polymer electrolyte polymer membrane samples. Table 2: Activation energies (Ea) and conductivity of pure PVA and PVA based electrospun polymer electrolyte complex membranes at common temperature Polymer electrolyte systems Activation energy (eV) Conductivity (S cm-1) Pure PVA 0.60 1.1210-9 PVA-PVP-KNO3-BaTiO3 (60-30-10-3) 0.54 3.7110-9 PVA-PVP-KNO3-BaTiO3 (60-30-10-6) 0.44 6.6110-8 PVA-PVP-KNO3-BaTiO3 (60-30-10-9) 0.41 1.9910-5 PVA-PVP-KNO3-BaTiO3 (60-30-10-12) 0.47 2.7510-6 PVA-PVP-KNO3-BaTiO3 (60-30-10-15) 0.48 4.5710-7 3.2. XRD analysis complexes of different compositions containing 3, 6, 9, 12 and 15 wt% of BaTiO3 as nano filler, X-ray diffraction (XRD) measurements is the most respectively. The XRD patterns for BaTiO3 filler, useful technique for determination of the nature of and KNO3 salt, are presented in figure 3(g-h). Figure the sample, crystallinity, phase identification, phase 3(a) shows two broad peaks at angles 2θ = 19.5° and changes of material, quantitative analysis of a 22.5° which indicates the amorphous nature of the mixture of gases, particle size analysis, pure PVA. Figure 3 (h) of KNO3 salt shows intense characterization of physical imperfections, and characteristic peaks at angles 2θ= 22.6°, 27.6°, crystal structure. XRD studies have been carried out 33.5°, 38.2°, 46.5°, 48.1° and 36.581° which in order to investigate the influence of addition of confirms the high crystalline nature of the ionic salt BaTiO3 filler on the structure of PVA-PVP blend KNO3. Comparative studies of the XRD patterns of polymer electrolyte systems to provide information pure PVA, BaTiO3 filler, KNO3 salt and PVA films about the presence of amorphous, crystalline or complexed with salt and filler, reveal that peaks semicrystalline regions, and occurrence of pertaining to pure KNO3 salt and BaTiO3 filler are complexation in the complexed solid polymer more intense as compared to those in PVA films electrolyte films. Figure 3(a-f) displays the X-ray complexed with KNO3 salt and BaTiO3 filler. This diffraction (XRD) patterns of pure PVA, PVA-PVP- shows that PVA, complexed with KNO3 salt and based blend composite polymer electrolyte BaTiO3 filler, is less crystalline compared to pure © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 163
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Investigation of structural and conductivity properties… KNO3 salt and BaTiO3 filler. X-ray diffraction filler in the amorphous region of polymers matrix analysis shows the decrease of crystallinity of the and inhibits the crystallization of PVA-PVP-KNO3- composite polymer matrix. BaTiO3 complexes. The decrease in degree of crystallinity of PVA complexed with salt and filler is caused by complexation of the salt and filler with PVA. The absence of crystalline peaks corresponding to KNO3 salt and BaTiO3 filler in h PVA complexed with KNO3 salt shows the absence of any uncomplexed salt and filler in the complexed polymeric electrolyte system. The highest ionic g conductivity value of the polymer electrolyte PVA- PVP-KNO3-BaTiO3 system with 9 wt% BaTiO3 is in accordance with the highest degree of amorphicity among the studied systems. As the filler contents f were increased from 3 to 15 wt% BaTiO3 in PVA, the crystallinity was shown to be increased. The Intensity (a. u.) incorporation of BaTiO3 filler in PVA has been e shown to increase the crystallinity of pure PVA. It can be noted that, above the optimum level (9 wt%) of filler content the intensity of the characteristic d peaks in the XRD patterns of the films again enhances with the increase of filler concentration in c the matrix and show the presence of very few less intense peaks at 2θ = 22.4°, 25.1°, 33.4°, 37.7°, b 50.3° and 63.2° in figure 3(e-f). The less intense peaks due to reduction of crystallinity which a observed in the XRD patterns of PVA-PVP-KNO3- BaTiO3 solid polymer electrolytes upon addition of 10 30 50 70 90 filler might be attributed to the presence of residual 2θ (degree) small particles of fillers. Figure 3: X-ray diffraction patterns of (a) pure PVA, It is observed that some characteristic peaks (b) PVA-PVP-KNO3-BaTiO3 (60-30-10-3), pertaining to KNO3 salt (e.g., at 2θ value of 46.5°) (c) PVA-PVP-KNO3-BaTiO3 (60-30-10-6), and BaTiO3 filler (e.g., at 2θ values of 66.7°) (d) PVA-PVP-KNO3-BaTiO3 (60-30-10-9), disappear, while other peaks corresponding to the (e) PVA-PVP-KNO3-BaTiO3 (60-30-10-12), KNO3 (e.g., at 2θ values of 27.6°, 48.1° and 52.1°) (f) PVA-PVP-KNO3-BaTiO3 (60-30-10-15), and BaTiO3 filler (e.g., at 2θ values of 23.6°, 38.6°, (g) pure BaTiO3 (h) pure KNO3 46.5°, and 56.9°) slightly displaced with respect to the original position of the peaks observed for pure Peaks pertaining to KNO3 salt and BaTiO3 filler components of complex polymer electrolyte systems are not found in the complex of PVA at lower (figure 3(a-h). The absence and shifting of peaks concentration of BaTiO3 filler, which indicates show that some interactions have taken place complete complexation between the polymer and between the different constituents of sample films. filler. It is found that the incorporation of filler The above mentioned analysis confirmed the (BaTiO3) into the PVA matrix causes increase in the absolute complexation of the dopants in the amorphous character of the sample and the intensity amorphous phase of the polymer matrices.[41] of the crystalline peaks of filler in the composite It is confirmed by the disappearance of polymer electrolyte membranes decreases and crystalline peaks that no excess KNO3 salt and broadens by increasing the BaTiO3 filler content BaTiO3 filler are present in the complexed solid (figure 3b-f) up to certain level (9 wt%), indicates polymer blend electrolyte films. This is supported by the amorphous structure of the electrolyte the ionic conductivity results already discussed in membrane. It was observed from the XRD analysis conductivity studies. that for the concentrations of the filler ranging from Addition of filler particles prevent the polymer 3 to 9 wt%, there are no sharp crystalline peaks chain reorganization, resulting in increase of pertaining to pure BaTiO3 filler appearing in the polymer amorphicity in the composite polymer complex that indicates the complete complexation of electrolyte membrane, which facilitates for higher © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 164
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Rahmat Gul et al. ionic conductivity.[42-43] The amorphous nature of 3135 cm-1 which assigned to the strong polymers, leading to high ionic conductivity, as intermolecular hydrogen bonded hydroxyl groups amorphous polymers has flexible backbone which (O-H) stretching vibration frequency of pure PVA is provides greater ionic diffusivity. [44] The higher shifted to lower frequency 3558-3000 cm-1, 3546- conductivity may be due to the larger surface area of 2960 cm-1, 3520-2928 cm-1 and 3533-2981 cm-1 in filler, which helps the faster movement of ion along the polymer complexes containing 3, 6, 9, and 12 the surface. wt% BaTiO3 filler, respectively. In addition to this, the C-H stretching of CH2 which showed an 3.3. FTIR analysis absorption frequency band at 3000-2806 cm-1 in pure PVA is shifted to lower frequency 2992-2762 FTIR spectroscopy is important in the investigation cm-1, 2941-2748 cm-1, 2851-2606 cm-1 and 2928- of polymer structure, since it provides information 2723 cm-1 in the polymer electrolytes systems about the complexation and interactions among containing 3, 6, 9, and 12 wt% BaTiO3 filler, various constituent i.e atoms or ions in the polymer respectively. The C-H bending of CH2 in pure PVA electrolyte systems. These interactions can induce observed absorption at 1512-1395 cm-1 is also found changes in the vibrational modes of the polymer to be shifted to lower wave numbers 1447-1315 electrolyte systems. The FTIR spectra were recorded cm-1, 1344-1169 cm-1, 1381-1307 cm-1, and 1612- at room temperature in the region of 400-4000 cm-1 1526 cm-1 in the polymer electrolyte systems in the transmittance mode. complexed with 3, 6, 9, and 12 wt% BaTiO3 filler, g respectively. Deformation is coupled to C-H wagging and gives rise to a shift of peak at 1319- 1180 cm-1 in pure PVA to lower wave numbers f 1315-1156 cm-1, 1164-998 cm-1, 1113-997 cm-1, and 1526-1429 cm-1 in the polymer electrolyte complex e systems containing 3, 6, 9, and 12 wt% BaTiO3 filler, respectively. The absorption frequency peak at Transmittance (arb. unit) d 884-791 cm-1 is corresponding to C–H rocking of pure PVA. This peak is shifted to 847-773 cm-1, c 892-805 cm-1, 847-743 cm-1 and 1000-997 cm-1, in polymer electrolyte systems doped with 3, 6, 9, and b 12 wt% filler, respectively. The C═O stretching at 1782-1680 cm-1 of pure PVA is found to be displaced to lower wave numbers 1744-1650 cm-1, 1718-1563 cm-1, 1615-1483 cm-1, and 1705-1612 a cm-1 in the complexed polymer electrolyte system containing 3, 6, 9, and 12 wt% BaTiO3 filler, respectively. C-C stretching occurring at 1166-977 3600 2600 1600 600 cm-1 in pure PVA is shifted to 1048-876 cm-1, 984- Wave number (cm-1) 892 cm-1, 984-871 cm-1 and 1396-1216 cm-1 in Figure 4: FTIR spectrum of (a) Pure PVA, complexed polymer electrolyte films containing 3, 6, (b) Pure PVP, (c) KNO3 salt and PVA-PVP-KNO3 9, and 12 wt% filler, respectively. (60-30-10) complex solid polymer electrolyte The characteristic vibration of C=N (Pyridine systems with, (d) 3 wt% BaTiO3, (e) 6 wt% BaTiO3, ring) appears as a very small peak at about 1653 (f) 9 wt% BaTiO3, (g) 12 wt% BaTiO3 cm-1 in the spectrum for pure PVP. The frequency band at about 964 cm-1 is corresponding to the out of The FTIR spectrum of the starting materials pure plane rings C-H bending of pure PVP. The peak PVA, pure PVP, KNO3 and the polymer complexes assigned to KNO3 has been displaced in the polymer doped with different concentrations of BaTiO3 filler electrolyte systems. The above alterations in the are shown in figure 4(a-g). The following changes in characteristic vibrational frequencies of pure the spectral features were observed after comparing poly(vinyl alcohol) PVA, PVP and KNO3 salt in the the spectrum of complexed PVA with that of pure FTIR spectra of polymer blend electrolyte complex PVA, PVP and KNO3. A broad and strong systems clearly indicate the interaction and complex absorption frequency band in the region of 3597- formation between PVA-PVP polymer blend matrix, © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 165
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Investigation of structural and conductivity properties… KNO3 salt and BaTiO3 filler. (TGA). Typical thermogravimetric analysis (TGA) curves in figure 5(a-e) shows the effect of variation 3.4. Thermal stability in the % by weight concentration of BaTiO3 filler on thermal stability of the pure PVA and PVA-PVP- The thermal stability of the PVA based KNO3-BaTiO3 composite polymer blend electrolyte nanocomposite polymer electrolyte membranes was membranes containing four different filler contents evaluated through thermogravimetric analysis viz. 3, 6, 9 and 12 wt% of BaTiO3. Pure PVA 10 3 wt% 6 wt% 9 wt% 8 12 wt% Weight (%) 6 4 2 0 30 130 230 330 430 530 Temperature (oC) Figure 5: TG curves of (a) pure PVA, (b) PVA-PVP-KNO3-BaTiO3 (60-30-10-3), (c) PVA-PVP-KNO3-BaTiO3 (60-30-10-6), (d) PVA-PVP-KNO3-BaTiO3 (60-30-10-9), (e) PVA-PVP-KNO3-BaTiO3 (60-30-10-12) From the given TGA data, it is obvious that the this region is relatively small and presumably thermal decomposition of the sample films occurs in attributed to the presence of absorbed residual a complicated way. TGA curves for these polymer moisture molecules during loading of the sample electrolyte systems show a gradual weight loss, up to films or due to impurities. Most of these absorbed 280, 306, 309, 312 and 322 °C for pure PVA and water molecules are supposed to be in a bound state, composite polymer electrolyte systems containing 3, rather than in the free molecular state.[46] No further 6, 9, and 12 wt% BaTiO3 filler, respectively. Above weight loss was noted above 100 °C until these temperatures, TGA curves show rapid weight irreversible thermal decomposition of sample films loss for these samples. This rapid weight loss is due started at around 280, 306, 309, 312 and 322 °C for to the degradation of the polymer electrolyte pure PVA and composite polymer electrolyte systems. The host polymer pure PVA sample is systems containing 3, 6, 9, and 12 wt.% BaTiO3 known to thermally stable up to 280 °C and displays filler, respectively. The second weight loss due to thermal decomposition above this temperature. It the actual decomposition of the film takes place at can be seen from TGA curves of PVA that no rapid around 250-400 °C corresponds to the breakage of weight loss occurs before 280 °C which clearly some portion of polymer chains and decomposition indicates that PVA is thermally stable up to 280 °C. of the main chains of the PVA.[47] The The rapid weight loss of the samples reflects the decomposition temperature of PVA was 280 °C. breakage of the side polymer chains.[45] The TGA This indicates that the sample film is thermally curve of the PVA based membrane showed two stable up to about 280 °C. That temperature consecutive weight losses arising from the processes increased to 306-322 °C with inorganic nano filler of thermal solvation, and thermal degradation of the addition. Figure 5(a-f) indicates that, with the polymer matrix. The first weight loss exhibited by increase in BaTiO3 filler content in composite all the sample films takes place before 100 °C in the complexed polymer electrolyte systems, degradation temperature range of 60-100 °C. The weight loss in temperature increases. The increase in degradation © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 166
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Rahmat Gul et al. temperature of these polymer electrolyte systems PVA polymer. FTIR analyses display the possible may be due to the increase in thermal stability with interactions between BaTiO3 filler and the host the addition of BaTiO3 filler. It was found that these polymer in the composite polymer electrolyte polymer electrolyte systems show stability up to systems. Morphological study shows microporous about 322 °C; above this temperature, these systems structure of the Nano fibrous polymer membranes display thermal degradation. Many researchers have because of incorporation of metal oxide filler which pointed out that incorporation of nanoparticles into a may be more effective to support remarkable ionic polymer matrix enhanced the membranes thermal conductivity. Based on these observations it can be stability for PVA. The presence of the BaTiO3 clearly suggested that BaTiO3 would be good filler nanofiller particles restricted the mobility of the for composite polymer electrolyte membranes. polymer chains, therefore, control thermal degradation of polymer electrolyte systems. Acknowledgment. The authors gratefully Obviously, it is clear from the above observations acknowledge the support of the School of Chemical that the thermal stability was appreciably increased Sciences, USM (Malaysia) and TWAS, to carry out by the addition of the metal oxide fillers and the the research work. One of the authors, Rahmat Gul, chemical crosslinking occurring between various acknowledges the University Sains Malaysia (USM) constituents of polymer electrolyte membranes. It and TWAS, for the award of Post-Doctoral could be concluded that electrospun nanocomposite Fellowship. polymer electrolyte systems with inorganic nanofiller BaTiO3 can be used as polymer electrolyte Conflict of interest and authorship confirmation in batteries and various other electrochemical form. All authors have participated in (a) devices applications because operating temperature conception and design, analysis and interpretation of these batteries in the range of 40-70 °C which is of the data; (b) drafting the article; and (c) approval fairly low compared to the thermal stability of the final version. This manuscript has not been temperature of synthesized electrolyte films viz. submitted to, nor is under review at, another journal 280-322°C. or other publishing venue. 4. CONCLUSIONS REFERENCES Nanocomposite complexed polymer electrolyte 1. J. E. Bauerle. Study of solid electrolyte polarization systems based on the blend of PVA-PVP with a by a complex admittance method, J. Phys. Chem. constant ratio of KNO3 salt were prepared for Solids., 1969, 30, 2657-2670. different concentrations of BaTiO3 by 2. J. Y. Sanchez, F. Alloin, C. P. Lepmi. Polymeric materials in energy storage and conversion, Mol. electrospinning technique. PVA composite polymer Cryst. Liq. Cryst., 1998, 324, 257-266. electrolyte membranes with various concentrations 3. P. V. Wright. Polymer electrolytes-the early days, filler are studied to investigate the effect of metal Electrochim. Acta, 1998, 43, 1137-1143. oxide filler concentration on polymer electrolyte 4. V. D. Noto, S. Lavina, G. A. Giffin, E. Negro. systems. The ionic conductivity value for various Polymer Electrolytes: Present, Past and Future, composite polymer electrolyte systems with Electrochim Acta., 2011, 57, 4-13. different content of BaTiO3 filler has been evaluated 5. T. Chen, Y. W. Chen-Yang. Recent development of at different temperatures. The maximum ionic the application of polymer electrolytes on polymer conductivity at 298 K (1.9910-5 S cm-1) has been lithium secondary batteries, Huaxue, 2004, 62, 445- 454. obtained for PVA-PVP-KNO3-BaTiO3 composite 6. J. Evans, C. A. Vincent. Electrochemical polymer electrolyte system prepared with 9 wt% measurement of transference numbers in polymer BaTiO3 filler. The composite polymer electrolyte electrolytes, Polymer, 1987, 28, 2324-2328. system having a maximum ionic conductivity value 7. H. Block, A. M. North. Dielectric relaxation in at room temperature display thermal stability up to polymer solutions, Adv. Mol. Relax., 1970, 1, 309. 312°C. The interaction between the BaTiO3 filler 8. C. Wang, Y. Xia, K. Koumoto, T. Sakai. All solid- and the polymer salt complex, reduction in state Li/LixMnO2 polymer battery using ceramic crystallinity and the dissolution of the salt were modified polymer electrolytes, J. Electrochem. Soc., confirmed by FTIR and XRD analyses after addition 2002, 149, A967-A972. of BaTiO3 filler. It has been found from XRD result 9. S. Ramesh. Conductivity and FTIR studies on PEO- LiX [X: CF3SO3-, SO42-] polymer electrolytes, that composite polymer electrolyte system with Spectrochim. Acta A, 2008, 69, 670-675. maximum ionic conductivity at room temperature 10. F. Croce, G. B. Appetecchi, L. Persi, B. Scrosati. have improved amorphous nature than that of pure © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 167
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Investigation of structural and conductivity properties… Nanocomposite polymer electrolytes for lithium Polymer Electrolyte Membranes Based on batteries, Nature, 1998, 394, 456-458. Structurally Modified PVA-PVP with Improved 11. A. M. Stephan, K. S. Nahm, T. P. Kumar, M. A. Alkali Stability, Polymer, 2010, 51, 4850-4859. Kulandainathan, G. Ravi, J. Wilson. Nanofiller 26. C. V. S. Reddy, X. Han, Q. Y. Zhu, L. Q. Mai, W. incorporated poly(vinylidene fluoride- Chen. Dielectric spectroscopy studies on (PVP + hexafluoropropylene) (PVDF-HFP) composite PVA) polyblend film, Microelectron. Eng., 2006, electrolytes for lithium batteries, J. Power Sources, 83, 281-285. 2006, 159, 1316-1321. 27. M. S. Michael, M. M. E. Jacob, S. R. S. Prabaharan, 12. Y. W. Chen-Yang, H. C. Chen, F. J. Lin, C. W. S. Radhakrishna. Enhanced Lithium-ion Transport Liao, T. L. Chen. Preparation and conductivity of in PEO-Based Solid Polymer Electrolytes the composite polymer electrolytes based on Employing a Novel Class of Plasticizers, Solid State poly[bis(methoxyethoxyethoxy)phosphazene], Ionics, 1997, 98, 167-174. LiClO4 and Al2O3, Solid State Ionics, 2003, 156, 28. J. L. Souquet, M. Levy, M. Duclot. A single 383-392. microscopic approach for ionic transport in glassy 13. G. B. Appetecchi, F. Croce, L. Persi, F. Ronci, B. and polymer electrolytes, Solid State Ionics, 1994, Scrosati. Transport and interfacial properties of 70/71, 337-345. composite polymer electrolytes, Electrochim. Acta, 29. S. Ramesh, A. K. Arof. Ionic conductivity studies of 2000, 45, 1481-1490. plasticized poly(vinyl chloride) polymer 14. C. C. Liang. Conduction Characteristics of the electrolytes, Mater. Sci. Eng. B, 2001, 85, 11-15. Lithium Iodide‐Aluminum Oxide Solid Electrolytes, 30. S. Rajendran, T. Uma. Lithium ion conduction in J. Electrochem Soc., 1973, 120, 1289. PVC-LiBF4 electrolytes gelled with PMMA, J. 15. S. L. Agrawal, P. K. Shukla, P. K. Srivastava. Power Sources, 2000, 88, 282-285. Influence of solvent on the ionic conductivity of 31. M. B. Armand, J. M. Chabagno, M. J. Duclot, P. PVA-NH4SCN complex, Bull Electrochem., 1996, Vashishta, J. N. Mundy, G. K. Shenoy. In Fast Ion 12, 727. Transport in Solids, Eds., North-Holland: New 16. F. Croce, G. B. Appetecchi, L. Persi, B. Scrosati. York, 1979, 131. Nanocomposite Polymer Electrolytes for Lithium 32. C. V. Subba Reddy, Q. Y. Zhu, Li-Q. Mai, W. Batteries, Nature, 1998, 394, 456-458. Chen. Optical, electrical and discharge profiles for 17. J. E. Weston, B. C. H. Steele. Effects of inert fillers (PVC+NaIO4) polymer electrolytes, J. Appl. on the mechanical and electrochemical properties of Electrochem., 2006, 36, 1051-1056. lithium salt-poly(ethylene oxide) polymer 33. S. D. Druger, A. Nitzam, M. A. Ratner. Generalized electrolytes, Solid State Ionics, 1982, 7, 75. hopping model for frequency-dependent transport in 18. W. Wieczoreck, Z. Florjanezyk, J. R. Stevens. a dynamically disordered medium, with applications Composite polyether based solid electrolytes, to polymer solid electrolytes, Phys. Rev. B, 1985, Electrochim Acta, 1995, 40, 2251-2258. 31, 3939. 19. B. K. Choi, K. H. Shin. Effects of SiC fillers on the 34. S. F. Johnston, I. M. Ward, J. Cruickshank, G. R. electrical and mechanical properties of Davies. Spectroscopic studies of triflate ion (PEO)16LiClO4 electrolytes, Solid State Ionics, association in polymer gel electrolytes and their 1996, 303, 86-88. constituents, Solid State Ionics, 1996, 90, 39-48. 20. J. R. MacCallum, C. A. Vincent. Eds. Polymer 35. I. Aibinssion, B. E. Mellander, J. R. Stevens. Ionic Electrolyte Reviews, Vols. 1 and 2; Elsevier: New conductivity in poly(propylene glycol) complexed York, 1987 & 1989. with lithium and sodium triflate, J. Chem. Phys., 21. Y. Liu, J. Y. Lee, L. Hong. In situ preparation of 1992, 96, 681-690. poly(ethylene oxide)-SiO2 composite polymer 36. G. B. Appetecchi, F. Croce, L. Persi, F. Ronci, B. electrolytes, J. Power Sources, 2004, 129, 303-311. Scrosati. Transport and interfacial properties of 22. M. R. Johan, O. O. Shy, S. Ibrahim, S. M. M. composite polymer electrolytes, Electrochim Acta, Yassin, T. Y. Hue, Effects of Al2O3 Nanofiller and 2000, 45, 1481-1490. EC Plasticizer on the Ionic Conductivity 37. F. Croce, L. Persi, B. Scrosati, F. Serraino-Fiory, E. Enhancement of Solid PEO-LiCF3SO3 Solid Plichta, M. A. Hendrickson. Role of the ceramic Polymer Electrolyte, Solid State Ionics 2011, 196, fillers in enhancing the transport properties of 41-47. composite polymer electrolytes, Electrochim Acta, 23. P. Mahanandia, K. K. Nanda, Anisotropic Electrical 2001, 46, 2457-2461. Transport Properties of Poly(Methyl Methacrylate) 38. B. Kumar, L. G. Scanlon. Polymer-ceramic Infiltrated Aligned Carbon Nanotube Mats, Appl. composite electrolytes: conductivity and thermal Phys. Lett., 2012, 100. history effects, Solid State Ionics, 1999, 124, 239- 24. Z. Ahmad, N. A. Al-Awadi, F. Al-Sagheer. Thermal 254. Degradation Studies in Poly(Vinyl 39. M. M. E. Jacob, E. Hackett, E. P. Giannelis. From Chloride)/Poly(Methyl Methacrylate) Blends, nanocomposite to nanogel polymer electrolytes, J. Polym. Degrad. Stabil., 2008, 93, 456-465. Mater. Chem., 2003, 13, 1-5. 25. J. Qiao, J. Fu, R. Lin, J. Ma, J. Liu. Alkaline Solid 40. Y. Tominaga, S. Asai, M. Sumita, S. Panero, B. © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 168
25728288, 2023, 2, Downloaded from https://onlinelibrary.wiley.com/doi/10.1002/vjch.202100050 by Readcube (Labtiva Inc.), Wiley Online Library on [02/05/2024]. See the Terms and Conditions (https://onlinelibrary.wiley.com/terms-and-conditions) on Wiley Online Library for rules of use; OA articles are governed by the applicable Creative Commons License Vietnam Journal of Chemistry Rahmat Gul et al. Scrosati. A novel composite polymer electrolyte: 44. R. Frech, S. Chintapalli. Effect of propylene effect of mesoporous SiO2 on ionic conduction in carbonate as a plasticizer in high molecular weight poly(ethylene oxide)-LiCF3SO3 complex, J. Power PEO-LiCF3SO3 electrolytes, Solid State Ionics, Sources, 2005, 146, 402-406. 1996, 85, 61-66. 41. D. R. MacFarlane, F. Zhou, M. Forsyth. Ion 45. S. J. Lue, J. Y. Chen, J. M. Yang. Effect of Air-Gap conductivity in amorphous polymer/salt mixtures, Distance on the Formation and Characterization of Solid State Ionics, 1998, 113-115, 193-197. Hollow Polyacrylonitrile (PAN) Nascent Fibers, J. Macromol, Sci. Part B: Physics, 2008, 47, 39. 42. P. R. Somani, R. Marimuthu, A. K. Viswanath, S. 46. I. Honma, O. Nishikawa, T. Sugimoto, S. Nomura, Radhakrishnan, Thermal degradation properties of H. Nakajima. High Temperature Proton Conducting solid polymer electrolyte (poly(vinyl Organic/Inorganic Nanohybrids for Polymer alcohol)+phosphoric acid)/methylene blue Electrolyte Membrane: Part II, Fuel Cells, 2002, 2, composites, Polym. Degrad. Stab., 2003, 79, 77-83. 52. 43. F. Croce, G. B. Appetecchi, L. Persi, B. Scrosati. 47. D. S. Kim, I. C. Park, H. I. Cho, D. H. Kim, G. Y. Nanocomposite polymer electrolytes for lithium Moon, H. K. Lee, J. W. Rhim. J. Ind. Eng. Chem., batteries, Nature, 1998, 394, 456-458. 2009, 15, 265. Coresponding author: Rahmat Gul School of Chemical Sciences, University Sains Malaysia 11800 Minden, Pulau Penang, Malaysia E-mail: rahmat388@yahoo.com. © 2023 Vietnam Academy of Science and Technology, Hanoi & Wiley-VCH GmbH www.vjc.wiley-vch.de 169