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FTIR AND IONIC CONDUCTIVITY STUDIES ON BLEND POLYMER ELECTROLYTES  [PDF]
J. Senthil,N.S. MINIMALA,GOVINDA NAGARAJAN,O. MAHENDRAN
International Journal of Engineering Science and Technology , 2011,
Abstract: Investigations on structural and conductivity properties of solid polymer complexes have attracted a high degree of attention. The main applications of solid polymer electrolytes (SPEs) are found in varioussecondary batteries and energy conversion units. In view of the abundant resources, low costs and relatively low reactivity of magnesium, solid-state batteries using magnesium metal are worthy of investigations. The polymer electrolytes were prepared using poly methyl methacrylate (PMMA), poly vinyl chloride (PVC) and magnesium chloride (MgCl2) by solvent casting technique. The complex formation and ionic conductivity were characterized by Fourier Transform Infra Red spectroscopy (FTIR) and impedance spectroscopy respectively.The FTIR studies provide the evidence of interaction of cation Mg2+ with the polymers. The maximum conductivity found for PMMA-MgCl2 is 0.57 x 10-7 Scm-1 at room temperature.
Electrical Impedance Response of Gamma Irradiated Gelatin based Solid Polymer Electrolytes Analyzed Using a Generalized Calculus Formalism  [PDF]
Tania Basu,Abhra Giri,Sujata Tarafdar,Shantanu Das
Physics , 2015,
Abstract: The electrical impedance response of Gelatin based solid polymer electrolyte to gamma irradiation is investigated by impedance spectroscopy. An analysis based on Poisson-Nernst-Plank model, incorporating fractional time derivatives is carried out. A detailed derivation for anomalous impedance function is given.The model involves boundary conditions with convolution of the fractional time derivative of ion density and adsorption desorption relaxation kinetics. A fractional diffusion-drift equation is used to solve the bulk behavior of the mobile charges in the electrolyte. The complex adsorption-desorption process at the electrode-electrolyte interface produces an anomalous effect in the system. The model gives a very good fit for the observed impedance data for this biopolymer based solid electrolyte in wide range of frequencies. We have compared different parameters based upon this model for both irradiated and unirradiated samples.
Poly(Acrylamide-Co-Acrylic Acid)-Zinc Acetate Polymer Electrolytes: Studies Based on Structural and Morphology and Electrical Spectroscopy  [PDF]
Mohd Faiz Hassan, Siti Zulaikha Mohd Yusof
Microscopy Research (MR) , 2014, DOI: 10.4236/mr.2014.22005
Abstract:

Solid polymer electrolytes (SPEs) of polyacrylamide-co-acrylic acid (PAA) as the polymer host and zinc acetate (ZnA) as an ionic dopant were prepared using a single solvent by the solution casting technique. The amorphous and crystalline structures of film were investigated by X-ray diffraction (XRD). The surface morphology of samples was examined by scanning electron microscopy (SEM). The composition and complex formation of films were characterized by Fourier transform infrared (FTIR) spectroscopy. The conductivity of the PAA-ZnA films was determined by electrochemical impedance spectroscopy. According to the XRD and FTIR analyses, all electrolyte films were in amorphous state and the existence of interaction between Zn2+ cations and the PAA structure confirms that the film was successfully prepared. The SEM observations reveal that the electrolyte films appeared to be rough and flat with irregularly shaped surfaces. The highest ionic conductivity (σ) of 1.82 × 10-5 Scm-1 was achieved at room temperature (303 K) for the sample containing 10 wt % ZnA.

Structural, Thermal, and Electrical Properties of PVA-Sodium Salicylate Solid Composite Polymer Electrolyte
Noorhanim Ahad,Elias Saion,Elham Gharibshahi
Journal of Nanomaterials , 2012, DOI: 10.1155/2012/857569
Abstract: Structural, thermal, and electrical properties of solid composite polymer electrolytes based on poly (vinyl alcohol) complexed with sodium salicylate were studied. The polymer electrolytes at different weight percent ratios were prepared by solution casting technique. The changes in the structures of the electrolytes were characterized by XRD, which revealed the amorphous domains of the polymer which increased with increase of sodium salicylate concentration. The complexion of the polymer electrolytes were confirmed by FTIR studies. Thermal gravimetric analysis (TGA) was used to study the thermal stability of the polymer below 523 K. The decomposition decreases with increasing sodium salicylate concentration. The conductivity and dielectric properties were measured using an impedance analyzer in frequency range of 20 Hz to 1 MHz and narrow temperature range of 303 to 343 K. The conductivity increased with increase of sodium salicylate concentration and temperature. The dielectric constant and dielectric loss increased with the increase in temperature and decreased with the increase in sodium salicylate concentration.
Polymer Electrolytes for Lithium/Sulfur Batteries  [PDF]
Yan Zhao,Yongguang Zhang,Denise Gosselink,The Nam Long Doan,Mikhail Sadhu,Ho-Jae Cheang,Pu Chen
Membranes , 2012, DOI: 10.3390/membranes2030553
Abstract: This review evaluates the characteristics and advantages of employing polymer electrolytes in lithium/sulfur (Li/S) batteries. The main highlights of this study constitute detailed information on the advanced developments for solid polymer electrolytes and gel polymer electrolytes, used in the lithium/sulfur battery. This includes an in-depth analysis conducted on the preparation and electrochemical characteristics of the Li/S batteries based on these polymer electrolytes.
PWA Doped SiO2 PEG Hybrid Materials of Class II  [PDF]
S. Grandi, P. Mustarelli, A. Carollo, C. Tomasi, E. Quartarone, A. Magistris
Materials Sciences and Applications (MSA) , 2010, DOI: 10.4236/msa.2010.15042
Abstract: Sol-gel is a promising technique for the synthesis of organic-inorganic hybrid materials of class II. One of the most interesting applications for these hybrid materials is as solid polymer electrolytes (SPEs). In particular, when doped with proton species they have potential applications in fuel cells. In this paper SiO2–PEG1500 hybrids of class II were prepared with different contents of SiO2 and phosphotungstic acid. The influence of the SiO2 content in the matrix has been studied. The samples were investigated by thermal analysis (TGA and DSC), X-ray diffraction, infrared spectros-copy (IR), scanning electron microscopy (SEM) and Impedance Spectroscopy.
Effect of Plasticizers on Structural and Dielectric Behaviour of [PEO + (NH4)2C4H8(COO)2] Polymer Electrolyte  [PDF]
Kamlesh Pandey,Nidhi Asthana,Mrigank Mauli Dwivedi,S. K. Chaturvedi
Journal of Polymers , 2013, DOI: 10.1155/2013/752596
Abstract: Improvements in ion transport property of polyethylene-oxide- (PEO-) based polymer electrolytes have been investigated, using different types of plasticizers. The effects of single and coupled plasticizers [i.e., EC, (EC + PC), and (EC + PEG)] on structural and electrical behavior of pristine electrolyte were studied by XRD, SEM technique, and impedance spectroscopy. The electrical conductivity of the best plasticized system was found to be 4?×?10?6?S/cm. Argand plots show dispersive nature of relaxation time or inhomogeneous space charge polarization of plasticized polymer electrolyte. 1. Introduction Recently, plasticized polymer electrolytes have been extensively used in the electrochemical devices, like secondary batteries, fuel cells, sensors, and smart windows. In order to improve their electrical and electrochemical properties for technical and industrial application, structural modification through plasticized polymer electrolytes is extensively used. Various techniques (like plasticization, copolymerization, etc.) have been adopted to achieve the desired objective of high ionic conduction and better stability of polymer composite electrolytes [1–3]. Large number of host polymer [e.g., polyethylene oxide (PEO), polymethylene methacrylate (PMMA), polypropylene oxide (PPO), polyvinyl alcohol (PVA), polyvinyl formal (PVF), etc.] [4–6] with different alkali and alkaline salts have been investigated in the past four decades. Among these polymers, PEO is the most studied polymeric system. The electrical conductivity of PEO is found relatively low at ambient temperature in comparison to the existing conventional liquid/hybrid electrolytes. The ionic conductivity of polymer electrolyte mainly depends upon (i) crystallinity of the material (ii) simultaneous cation and anion motion, and (iii) the ion-pair formation (anion complex-cation interaction). To overcome these problems, various approaches have been made to modify the structure of polymer electrolyte in the last three decades. Ammonium adipate (NH4)2C4H8(COO)2 contains smaller size cation (H+) with larger size anion which can easily dissociate and provide higher protonic conduction [7]. The addition of plasticizers in polymer electrolyte is one of the most effective approaches to improve the mobility of ionic or/and the interfacial interaction among ionic and polar groups in polymer chains. The choice of plasticizer and its concentration can affect film permeability and mechanical properties [8, 9]. The other advantage of plasticization is to modify the polymeric matrix and provide the enhanced
Characterization of PVC/PEMA Based Polymer Blend Electrolytes
S. Rajendran, M. Ramesh Prabhu, M. Usha Rani
International Journal of Electrochemical Science , 2008,
Abstract: Polymer electrolyte membranes comprising of poly (ethyl methacrylate)/ poly (vinyl chloride), propylene carbonate (PC) as plasticizer and LiClO4 as salt were prepared by solvent casting technique. XRD, FTIR and SEM studies have been made to investigate the structural, complexation and variation in film morphology of the polymer electrolyte. The maximum ionic conductivity value 3.454x10-3 S/cm has been observed for PVC (5)-PEMA (20)-PC (67) - LiClO4 (8 wt %) system at 303K using ac impedance spectroscopic technique. Also, the TG/DTA studies showed the thermal stability of the film.
Electrical Conduction Mechanism in Solid Polymer Electrolytes: New Concepts to Arrhenius Equation  [PDF]
Shujahadeen B. Aziz,Zul Hazrin Z. Abidin
Journal of Soft Matter , 2013, DOI: 10.1155/2013/323868
Abstract: Solid polymer electrolytes based on chitosan NaCF3SO3 have been prepared by the solution cast technique. X-ray diffraction shows that the crystalline phase of the pure chitosan membrane has been partially disrupted. The fourier transform infrared (FTIR) results reveal the complexation between the chitosan polymer and the sodium triflate (NaTf) salt. The dielectric constant and DC conductivity follow the same trend with NaTf salt concentration. The increase in dielectric constant at different temperatures indicates an increase in DC conductivity. The ion conduction mechanism follows the Arrhenius behavior. The dependence of DC conductivity on both temperature and dielectric constant ( ) is also demonstrated. 1. Introduction Ion conducting polymers are an active area of study in materials research. They are prepared by complexing polymers containing polar groups with alkali metal salts [1]. Being light weight and flexible [2, 3], attempts have been made to use solid polymer electrolytes in solid-state electrochemical devices such as batteries, fuel cells, electrochromic displays, and smart windows [4]. Polymer electrolytes usually contain both crystalline and amorphous phases. It has been reported that the ion conduction takes place primarily in the amorphous phase [5]. Chitosan is a derivative of chitin which can be obtained from crab and shrimp shells. Chitosan is produced from deacetylation of chitin to overcome the solubility limitation of chitin in common solvents [6]. Due to the NH2 and OH functional groups that can serve as conjunction sites, chitosan is a good sorbent with high affinity for transition metal ions [7]. Chitosan has good film forming ability, porous scaffolds, and hydrogels [8]. Ion-conducting polymer electrolytes based on chitosan have also been reported [9–16]. From the fundamental point of view, ionic conduction in polymer electrolytes is still poorly understood. Ion transport is complex and depends on factors such as salt concentration, dielectric constant of host polymer, degree of salt dissociation and ion aggregation, and mobility of polymer chains [17]. Dielectric analysis of ion conducting polymer electrolytes can provide information on ion transport behavior and ionic/molecular interaction in solid polymer electrolytes [18]. This is due to the fact that dielectric constant is both frequency and temperature dependent [19]. Recently Petrowsky and Frech [20, 21] hypothesized that the DC conductivity is not only a function of temperature, but also is dependent on the dielectric constant in organic liquid electrolytes. They have
PREPARATION AND CHARACTERISTICS OF NOVEL HYPERBRANCHED PEU-BASED GEL POLYMER ELECTROLYTES
WU,CHUAN; WU,FENG; BAI,YING; FENG,TING; PAN,CHUNHUA; YE,LIN; FENG,ZENGGUO;
Journal of the Chilean Chemical Society , 2009, DOI: 10.4067/S0717-97072009000300020
Abstract: gel polymer electrolytes (gpes) based on hyperbranched poly (ether urethane) (pheu) were prepared from the reaction of the hyperbranched polyether (phemo) with different dusocyanates in liquid electrolyte. the ionic conductivities and transference number of the gpes were investigated by altemating current (ac) impedance and multi-potential steps. it is found that the ionic conductivities of gpes were influenced by dusocyanate structure, lithium salt concentration and addition amount of liquid electrolyte. sample pum-0.5m-80% originated from 4, 4-diphenylmethane dusocyanate (mdi) as the hard segment shows the highest ionic conductivity of 2.41 x10-3 s·cm-1 at ambient temperature. the lithium ion transference number is 0.7. inaddition, small molecules of liquid electrolyte were perfectly entrapped by polymer matrix, and liquid leakage in lithium ion battery was avoided.
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