K. Karuppasamy

Effect of nanochitosan on electrochemical, interfacial and thermal properties of composite solid polymer electrolytes

PEO-based solid polymer electrolyte films with various concentrations of nanochitosan as filler and LiCF3SO3 as salt were prepared by membrane hot-press technique. Nanochitosan was prepared from chitosan by conventional chemical cure method. The prepared composite membranes were characterized by FT-IR, XRD, thermal, SEM, AFM analyses, electrochemical impedance spectroscopy, cyclic voltammetry and compatibility studies. The ionic conductivity and thermal stability of the polymer membranes were enhanced significantly by addition of nanofiller. The compatibility studies reveal that filler incorporated membrane is better compatible with lithium interface than filler free electrolyte.

Combined effect of nanochitosan and succinonitrile on structural, mechanical, thermal, and electrochemical properties of plasticized nanocomposite polymer electrolytes (PNCPE) for lithium batteries

A sequence of novel plasticized polymer nanocomposite electrolyte systems based on polyethylene oxide (PEO) as polymer host, LiCF3SO3 as salt, and a variety of concentrations of nanochitosan as inert filler, succinonitrile as a solid non-ionic plasticizer has been prepared. The prepared membranes were subjected to X-ray diffraction, FT-IR, tensile strength, morphological studies, thermal analysis, AC ionic conductivity measurement, and interfacial analyses. The combined effect of succinonitrile and nanochitosan on the electrochemical properties of polymer electrolytes has been studied, and it was confirmed that the ionic conductivity is significantly increased. The maximum ionic conductivity of the plasticized nanocomposite polymer electrolytes are found to be in the range of 10−2.8 S/cm. Besides, the interfacial stability also shows a significant improvement. The tensile measurement and thermal analysis results illustrate that the electrolytes based on that polymer host possess good mechanical and thermal stabilities.

A Review on PEO Based Solid Polymer Electrolytes (SPEs) Complexed with LiX (X=Tf, BOB) for Rechargeable Lithium Ion Batteries

Nanocomposite polymer electrolytes (NCPEs) have been playing a considerable role in the development of alternative clean and sustainable energy technologies. This review article summarizes the recent research progress on the synthesis and characterization of NCPEs and its application in lithium ion battery based energy storage devices. First, an introduction on the properties, synthesis strategies and use of NCPEs is briefly given, followed by a state-of-the-art review on the preparation of NCPEs and their electrochemical properties in lithium ion battery (LIB) applications. Finally, the prospects and future challenges of NCPEs for energy storage are discussed

High-mobility and low-operating voltage organic thin film transistor with epoxy based siloxane binder as the gate dielectric

This paper reports the fabrication of pentacene-based organic thin-film transistors using a dielectric material, Dynasylan ®SIVO110. The devices exhibit excellent performance characterized by a low threshold voltage of −1.4 V (operating voltage: 0 to −4 V) together with a mobility of 1.9 cm2 V−1s−1. These results are promising because it uses only a single layer of dielectric without performing any intermediate treatment. The reason is attributed to the high charge storage capacity of the dielectric (κ ∼ 20.02), a low interfacial trap density (2.56 × 1011cm−2), and favorable pentacene film morphology consisting of large and interconnected grains having an average size of 234 nm.

Ionic Conductivity and Dielectric Studies of Chitin Nanofiber (CNF) Incorporated PMMA Based Polymer Electrolytes

Chitin nanofibers (CNF) are synthesized from shrimp cell chitin by stepwise purification and acid hydrolysis method. PMMA based polymer electrolytes complexed with LIN (CF3SO2)2 and chitin nanofibers as nanofiller have prepared by membrane hot-press technique. The prepared composite electrolytes are subjected to FT-IR, ac impedance, dielectric and modulus analyses. The incorporation of nanofiller in the polymer matrix increases the conductivity by an order of magnitude compared with filler free electrolytes. The complexation behavior of the composite polymer electrolytes are investigated by ATR FT -IR spectroscopy. The electric modulus analysis and dielectric studies of polymer electrolytes revealed that the non Debye dielectric relaxation nature.

Evaluation of the Corrosion Resistance Properties of Electroplated Chitosan-Zn1−xCuxO Composite Thin Films

Novel chitosan–zinc copper oxide (Zn1−xCuxO) composites were electrochemically synthesized through galvanostatic deposition. The prepared chitosan-based composite thin films were elaborately investigated to determine their structural, morphological, compositional, impedance, and corrosion properties. X-ray diffraction analysis was performed to reveal their structural orientation of composite thin films. Energy dispersive analysis by X-ray evidently confirmed the existence of Zn, Cu, and O in the composite thin films. Nyquist plots revealed that the chitosan-Zn1−xCuxO thin films had obvious semi-circular boundaries, and higher resistance was observed for chitosan-ZnO due to the grain boundary effect. Corrosion properties were evaluated using both an electrochemical method and the ASTM weight gain method, which revealed good corrosion rates of 34 and 35 × 10−3 mm/y, respectively, for chitosan-ZnO thin film.

Effect of nanochitosan and succinonitrile on the AC ionic conductivity of plasticized nanocomposite solid polymer electrolytes (PNCSPE)

In the present study, the filler chitosan was converted into nanochitosan by ionotropic gelation method. Plasticized nanocomposite solid polymer electrolytes (PNCSPE) composed of poly ethylene oxide as host polymer, LiBOB (lithium bis(oxalatoborate)) as salt, SN as plasticizer and nanochitosan as filler were prepared by membrane hot-press technique. Succinonitrile and nanochitosan incorporation in PEO-LiBOB matrix enhanced the room temperature ionic conductivity. The highest ionic conductivities were found to be in the order of 10−3.2 S/cm.

Recent Advances in Metal Chalcogenides (MX; X = S, Se) Nanostructures for Electrochemical Supercapacitor Applications: A Brief Review

Supercapacitors (SCs) have received a great deal of attention and play an important role for future self-powered devices, mainly owing to their higher power density. Among all types of electrical energy storage devices, electrochemical supercapacitors are considered to be the most promising because of their superior performance characteristics, including short charging time, high power density, safety, easy fabrication procedures, and long operational life. An SC consists of two foremost components, namely electrode materials, and electrolyte. The selection of appropriate electrode materials with rational nanostructured designs has resulted in improved electrochemical properties for high performance and has reduced the cost of SCs. In this review, we mainly spotlight the non-metallic oxide, especially metal chalcogenides (MX; X = S, Se) based nanostructured electrode materials for electrochemical SCs. Different non-metallic oxide materials are highlighted in various categories, such as transition metal sulfides and selenides materials. Finally, the designing strategy and future improvements on metal chalcogenide materials for the application of electrochemical SCs are also discussed.

A Rapid One-Pot Synthesis of Novel High-Purity Methacrylic Phosphonic Acid (PA)-Based Polyhedral Oligomeric Silsesquioxane (POSS) Frameworks via Thiol-Ene Click Reaction

Herein, we demonstrate a facile methodology to synthesis a novel methacrylic phosphonic acid (PA)-functionalized polyhedral oligomeric silsesquioxanes (POSSs) via thiol-ene click reaction using octamercapto thiol-POSS and ethylene glycol methacrylate phosphate (EGMP) monomer. The presence of phosphonic acid moieties and POSS-cage structure in POSS-S-PA was confirmed by Fourier transform infrared (FT-IR) and nuclear magnetic resonance (1H, 29Si and 31P-NMR) analyses. Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrum of POSS-S-PA acquired in a dithranol matrix, which has specifically designed for intractable polymeric materials. The observed characterization results signposted that novel organo-inorganic hybrid POSS-S-PA would be an efficacious material for fuel cells as a proton exchange membrane and high-temperature applications due to its thermal stability of 380 °C.

Effect of Electron Beam Irradiation on the Mechanical and Electrochemical Properties of Plasticized Polymer Electrolytes Dispersed with Nanoparticles

The effect of electron beam irradiation on electrical, thermal, mechanical and morphological properties of plasticized polymer electrolytes was investigated. A significant improvement in the mechanical strength without reduction in ionic conductivity was observed for the irradiated polymer electrolytes. DSC studies showed that the thermal behavior of the polymer electrolytes was improved by the addition of filler and by irradiation. SEM studies revealed a significant improvement in surface morphology of the polymer electrolyte after irradiation. The results are presented herein.