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The effect of blending polyethylene oxide with poly (vinylidene fluoride)–lithium aluminum germanium phosphate (LAGP) composite and in-situ porosity generation on the electrochemical performance of polymer electrolytes based on non-woven fibrous mats is studied. Electrospinning process parameters are controlled to get a fibrous membrane consisting of bead-free, multilayered, three dimensional network structure of ultrafine fibers. The electrospun membranes are subjected to a preferential polymer dissolution process to prepare a highly porous structure. The membranes show high surface roughness with uniformly sized and distributed pores on the fibers. The membranes with good mechanical strength, thermal stability and high porosity exhibit high swelling when activated with liquid electrolyte. The prepared composite polymer electrolytes show high ionic conductivity. The addition of the glass ceramic improves the mechanical and thermal stability, while blending and in-situ porosity generation improves the ionic conductivity, charge–discharge performance, cycling stability, interface properties and compatibility with lithium electrode.

The advantageous properties of both solid soft matter electrolytes and polymer gel electrolytes (PGEs) are combined to develop a electrospun polymer composite electrolyte (PCE) for lithium ion batteries , based on addition of butanedinitrile (BDN, the plastic crystal) to poly(vinylidenefluoride- co -hexafluoropropylene) {P(VdF- co -HFP)} (semi crystalline polymer). Polymer composite electrolytes are prepared by activating the fibrous membrane with 1 M LiPF 6 in EC/DEC. The electrochemical characterization shows that the addition of BDN significantly improves the ionic conductivity of composite electrolytes even at lower temperatures due to the active role played by BDN in ion conduction. Also the compatibility of the polymer composite electrolyte with lithium electrode improves by incorporation of BDN. Galvanostatic cycling test demonstrates the suitability of these polymer composite electrolytes for lithium ion batteries in both Li/PCE/LiFePO 4 (half cell) and LTO/PCE/LiFePO 4 (full cell) configurations. The addition of BDN improves the charge discharge performance and cycling stability of the polymer composite electrolytes.

Here we report the fabrication and performance of a superoleophilic and anti-bacterial nonwoven nanofibrous poly(acrylonitrile-co-butadiene-co-styrene) [ABS]/ZnO electrospun nanocomposite membrane. The electrospun ABS membrane was decorated with floral ZnO nanoparticles (NPs) by a post-treatment method. The pristine ABS and nanocomposite membranes showed super oleophilic nature and could selectively separate different oils from the oil–water mixture by a gravity-driven technique. The ZnO NPs in the nanofiber could enhance the oil flux and also imparted anti-bacterial activity to electrospun ABS membrane against Escherichia coli and Staphylococcus aureus. The current nanofibrous system can be a good candidate for multi-functional oil-water separation.

Effect of poly(ethylene oxide) on the electrochemical properties of polymer electrolyte based on electrospun, non-woven membrane of PVdF is demonstrated. Electrospinning process parameters are controlled to get a fibrous membrane consisting of bead-free, uniformly dispersed thin fibers with diameter in the range of 1.5–1.9 μm. The membrane with good mechanical strength and porosity exhibits high uptake when activated with the liquid electrolyte of lithium salt in a mixture of organic solvents. The polymer gel electrolyte shows ionic conductivity of 4.9 × 10−3 S cm−1 at room temperature. Electrochemical performance of the polymer gel electrolyte is evaluated in Li/polymer electrolyte/LiFePO4 coin cell. Good performance with low capacity fading on charge–discharge cycling is demonstrated.

Two distinct mesoporous nanostructures, that is, rod and sheet cobalt oxalate (CoC2O4), have been synthesized via facile chimie douce precipitation technique. The selective interaction between solvent type and crystallographic planes of the metal ion is the key factor in morphological variations. The morphology and microstructure are studied by high-resolution transmission electron microscopy. Structural characterization of the materials has been carried out by X-ray diffraction and confirmed phase pure CoC2O4·2H2O formation. The critical dehydration process of CoC2O4·2H2O led to anhydrous CoC2O4, and its thermal properties are investigated by thermogravimetric analysis. Electrochemical properties of anhydrous CoC2O4 in half-cells are studied by cyclic voltammetry, galvanostatic charge–discharge cycling, and electrochemical impedance spectroscopy. The studies showed that initial discharge capacity of anhydrous CoC2O4 nanorods and sheets is 1599 and 1518 mA h g–1, respectively, at 1C-rate. Anhydrous CoC2O4...

Hybrid organic–inorganic polymer gel electrolytes (PGEs) based on polymer–clay nanocomposite microporous membrane containing 1 M lithium hexafluorophosphate (LiPF6) in ethylene carbonate/diethyl carbonate (EC/DEC) are fabricated and their electrochemical characteristics in lithium ion batteries are studied. Poly(vinylidene fluoride) (PVdF)–clay nanocomposite membrane containing different clay loading are prepared by phase inversion method. Aqueous suspension of montmorrillonite (MMT) clay in dimethyl acetamide (DMAc) is used as the nano-clay. The morphology of the clay dispersion with sonication time is studied by environmental scanning electron microscope (E-SEM). The intercalation/exfoliation of polymer–clay nanocomposite is characterized by X-ray diffraction (XRD). Differential scanning calorimetry (DSC) and thermal gravimetric analysis are used for the evaluation of thermal properties. DSC analysis shows that crystallinity of nanocomposite decreases with increasing nano-clay content. The effect of clay on the membrane morphology, ionic conductivity and electrochemical properties of the PGEs in lithium ion rechargeable batteries are studied and results are compared. Incorporation of 2 wt.% nano-clay in PGE enhances its ionic conductivity from 0.78 to 3.08 mS cm−1 at room temperature. Li-ion half cell comprising of Li/PVdF–clay(2 wt.%)-PGE/LiMn2O4 delivers high charge–discharge capacity (∼120 mAh g−1) and shows stable cycle performance.

A new approach for fabricating polymer gel electrolytes (PGEs) based on electrospun poly(vinylidenefluoride-co-hexafluoropropylene) {P(VdF-co-HFP)} incorporated with layered nanoclay has been employed to enhance the ionic conductivity and electrochemical properties of P(VdF-co-HFP) without compromising its mechanical strength. The effect of layered nanoclay on properties of membranes has been evaluated by X-ray diffraction (XRD), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Surface morphology of the membranes has been studied using field-emission scanning electron microscopy (FE-SEM). Polymer gel electrolytes are prepared by soaking the fibrous membrane into 1 M LiPF6 in EC/DEC. The electrochemical studies show that incorporation of layered nanoclay into the polymer matrix greatly enhanced the ionic conductivity and compatibility with lithium electrodes. The charge–discharge properties and cycling performance of Li/LiFePO4 cells comprising nanocomposite polymer gel electrolytes have been evaluated at room temperature.

One dimensional TiO2-B nanorods are synthesized by a conventional hydrothermal approach under highly concentrated alkali hydroxide solutions. Various characterization techniques such as X-ray diffraction, Raman studies, BET surface area measurements, scanning electron microscopy and transmission electron microscopy (TEM) are utilized. Electrochemical Li-insertion properties are evaluated by means of half-cell configuration (Li/TiO2-B) which delivered a discharge capacity of 195 mA h g−1 at a current density of 150 mA g−1 under ambient temperature conditions. The test cell, Li/TiO2-B, displayed good cycling profiles up to 500 cycles with columbic efficiency over 99.5%. Full-cell, LiMn2O4/TiO2-B, is fabricated and tested both in conventional liquid and PVdF-HFP membranes at a current density of 150 mA g−1 and exhibited an excellent cycleability up to 1000 cycles at an operating potential of ∼2.5 V. The results demonstrate the improved electrochemical performance and durability of one dimensional nanostructures i.e. TiO2-B nanorods and electrospun membranes during prolonged cycling. In addition, ex-situ TEM analysis revealed the retention of nanorod morphology along with the crystalline structure after 1000 cycles in full-cell assembly, which ensures excellent long-term cycleability of TiO2-B anodes.

Mesoporous iron oxalate (FeC(2)O(4)) with two distinct morphologies, i.e., cocoon and rod, has been synthesized via a simple, scalable chimie douce precipitation method. The solvent plays a key role in determining the morphology and microstructure of iron oxalate, which are studied by field-emission scanning electron microscopy and high-resolution transmission electron microscopy. Crystallographic characterization of the materials has been carried out by X-ray diffraction and confirmed phase-pure FeC(2)O(4)·2H(2)O formation. The critical dehydration process of FeC(2)O(4)·2H(2)O resulted in anhydrous FeC(2)O(4), and its thermal properties are studied by thermogravimetric analysis. The electrochemical properties of anhydrous FeC(2)O(4) in Li/FeC(2)O(4) cells are evaluated by cyclic voltammetry, galvanostatic charge-discharge cycling, and electrochemical impedance spectroscopy. The studies showed that the initial discharge capacities of anhydrous FeC(2)O(4) cocoons and rods are 1288 and 1326 mA h g(-1), respectively, at 1C rate. Anhydrous FeC(2)O(4) cocoons exhibited stable capacity even at high C rates (11C). The electrochemical performance of anhydrous FeC(2)O(4) is found to be greatly influenced by the number of accessible reaction sites, morphology, and size effects.

This chapter aims at exploring the revolutionary field of nanotechnology and some of its promising aspects in polymer nanocomposites in view of preparation, characterization, materials properties, and processing of polymer layered silicate nanocomposites. These materials are attracting considerable interest in polymer science research. Polymer layered silicate nanocomposites are an important class of hybrid, organic/inorganic materials with substantially improved mechanical, thermal, and thermomechanical properties in comparison to pristine polymers. In addition, they also show superior ultraviolet (UV) as well as chemical resistance and are widely being investigated for improving gas barrier and flame retardant properties. Hectorite and montmorillonite are among the most commonly used smectite-type layered silicates for the preparation of polymer–clay nanocomposites. Smectites are a valuable mineral class for industrial applications due to their high cation exchange capacities, surface area, surface reactivity, adsorptive properties, and, in the case of hectorite, high viscosity and transparency in solution. A wide range of polymer matrices are explored for the preparation of polymer–clay nanocomposites, however, this chapter deals with special emphasis on biodegradable polymers––cellulose and natural rubber. Also, the chapter describes the common synthetic techniques in producing polymeric layered silicate nanocomposites, its properties, and applications.

Increasing demand for higher energy density and higher-power energy-storage devices from the portable power market and the automobile and telecommunication industries have led to the search for novel materials for electrodes or electrolytes that offer higher capacities and energy densities and better performance than the electrochemical energy-storage devices available today. It is recognized that these requirements cannot be met solely by the capabilities of conventional systems and energy materials. Nanomaterials, a cutting-edge technology, can serve as an alternative to traditional materials. Among these, carbon nanotubes (CNTs) and their hybrid nanostructures have been extensively studied in electrochemical energy storage devices such as lithium-ion batteries (LIBs), supercapacitors, solar cells, and fuel cells as ideal electrode materials. This is because of their unique, one-dimensional (1D) tubular structure and high surface area, aspect ratio, chemical stability, electrical, and thermal conductivities, along with their extremely high mechanical strength. Studies show that CNTs are capable of greatly improving the electrochemical characteristics of energy-storage systems, with enhanced energy conversion and storage capacities. This chapter discusses recent advances in lithium-ion/air batteries based on CNTs and their functionalized derivatives for electrochemical energy storage.

This chapter mainly reviews the concept, properties and processing, and design method of the eco-friendly polymer nanocomposite (EPN), which is generally biodegradable and renewable. The major attractions of EPN are that they are environmentally friendly, sustainable, and degradable. These polymer composites can be easily composted or disposed without harming the environment. Some efforts have been made on attaining biodegradable reinforcing fillers giving improved performance of composites. Another concern is focused on employing recyclable synthetic fibers with thermoplastic composites to reduce the waste of fillers, and also some research is devoted to reusing or recycling the whole composites for the similar purpose. Simultaneously, people also would like to make composites manufactured with traditional production process become eco-friendly by extra reprocessing. Throughout the stages of development––design, appraisal, manufacture, use, reuse–recycling, and disposal––researchers are supposed to be fully engaged in reducing waste as much as possible, keeping in mind the environment all the time. A series of natural or synthetic materials have been used, such as cellulose, thermoplastic starch, etc. The challenge posed by eco-friendly composites also needs considerable attention in terms of poor bonding between matrix and fillers, loose control of fiber orientation, and difficulty in shaping nanoscale particles.

Carbon nanotubes (CNTs) exhibit a unique combination of electrical, mechanical, and magnetic properties as well as nanometer-scale diameter and high aspect ratio, which make them an ideal reinforcing agent for high-strength polymer composites. However, there is still challenge to achieve the simple and economical method for improving the dispersion and solubilization of CNTs. To improve the dispersion of CNTs, several approaches have been applied by using covalent and noncovalent functionalization methods. Herein, in particular, we focused on CNT functionalization using dendritic polymer and click chemistry approach. The impact of CNT dispersion on the property improvement of composite materials is discussed. In particular, the polyurethane block copolymer-CNT composites are discussed in details.

Unique cocoon- and rod-shaped alpha-phase ferric oxide, hematite (α-Fe2O3) is prepared by a simple, scalable and surfactant-free chimie douce synthesis. The structure and morphology is confirmed by x-ray diffraction, field-emission scanning electron microscopy and high-resolution transmission electron microscopy. The electrochemical properties of α-Fe2O3 anodes are investigated using cyclic voltammetry, galvanostatic charge-discharge cycling and electrochemical impedance spectroscopy. The mesoporous α-Fe2O3 exhibited an initial discharge capacity >1741 mAh/g with excellent cycling performance and rate capabilities. The solvent used for the preparation of α-Fe2O3 plays a key role in determining the morphology of the materials, which greatly influenced its electrochemical properties. Published version

The aim of the present work is to prepare a novel polymer electrolyte (PE) based on multi component polymer blend of polyacrylonitrile (PAN), poly(methyl methacrylate) (PMMA) and polystyrene (PS) with varying compositions by electrospinning. Structural characterization is carried out using X-ray diffraction (XRD). The thermal and crystalline properties of the blend are studied by thermo-gravimetric analysis (TGA) and differential scanning calorimetry (DSC), respectively. Morphology of the membrane is examined by field emission scanning electron microscope (FE-SEM). The voids and cavities generated by the interlaying of the fibers are effectively utilized for the preparation of PE by loading with lithium hexafluorophosphate (LiPF6) dissolved in ethylene carbonate (EC)/diethyl carbonate (DEC). The ionic conductivity of the polymer blend electrolyte is studied by varying the PMMA and PS content in the PAN matrix. The blend polymer electrolyte shows ionic conductivity of about 3.9 × 10(−3) S cm(−1). The performance evaluation in coin cells show good charge–discharge properties and stable cycle performance under the test conditions. The result shows that the prepared polymer blend electrolytes are promising materials for lithium ion batteries. Accepted version