Upshot of Concentration of Zirconium (IV) Oxynitrate Hexa Hydrate on Preparation and Analyses of Zirconium Oxide (ZrO2) Nanoparticles by Modified Co-Precipitation Method.

In the present work, pure nanocrystalline monoclinic Zirconia (ZrO2) has been successfully synthesized and optimized by the modified co-precipitation method. The concentration of raw material has been optimized with the fixed amount of precipitation agent (Potassium hydroxide KOH). The thermal history of the precursor has been examined through TG/DTA analysis. All the samples are subjected to study the structure, fingerprints of the molecular vibrations, and morphology analyses. The representative sample has been analyzed through Transmission Electron Microscope (TEM) and X-ray Photo Electron Spectroscopy (XPS) analyses. The as-prepared sample exhibits the better crystallinity and surface morphology with lesser particle size (190 nm) when the raw material concentration is 0.2 M. The as-prepared ZrO2 filler (0, 3, 6, 9, and 12 wt.%) is spread through the enhanced polymer electrolyte P(S-MMA) (27 Wt.%)-LiClO4 (8 wt.%)-EC + PC (1;1 of 65 wt.%) complex system via solution casting method. The as-synthesized electrolyte films are examined via complex impedance analysis. P(S-MMA) (27 wt.%)-LiCIO4 (8 wt.%)-EC + PC (1 ;1 of 65 wt.%)-6 wt.% of ZrO2 shows the high ionic conductivity 2.35 × 10-3 Scm-1. Temperature-dependent ionic conductivity studies obey the non-linear behavior. The enhanced ZrO2 has been expected to enhance the other electrochemical properties of the lithium secondary battery.

Carbon Wrapping Effect on Sulfur/Polyacrylonitrile Composite Cathode Materials for Lithium Sulfur Batteries.

A sulfur-Polyacrylonitrile (PAN)-acetylene black (AB) composite was synthesized via thermal treatment processes. The as-prepared ternary composite was characterized by expending transmission electron microscopy (TEM), X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET) and electrochemical investigations. The improved electrochemical performance can be attributed to the formation of PAN layer, which can keep a tight contact between carbon and sulfur which leads to improve the conductivity. Moreover, the PAN can also act as a flexible cushion to accommodate volume changes of sulfur cathode as well as a barrier to trap soluble polysulfide intermediates during the charge-discharge process. The PAN-S-AB composite exhibits discharge capacity of 620 mAh/g even after 50 cycles with appreciable sustainability. Therefore, the resulting PAN/S/AB composite exhibited as a desirable cathode material for Li-S battery with great performance.

Synthesis and Electrochemical Performance of PEG-MnO2-Sulfur Composites Cathode Materials for Lithium-Sulfur Batteries.

Lithium-Sulfur (Li-S) batteries have been achieved great attention in recent years owing to its high theoretical capacity (1675 mAh/g) and energy density (2600 Wh/kg). PEG embedded MnO2/Sulfur composite was prepared via solid state reaction method. The composite was characterized by Transmission electron microscopy, scanning electron microscopy and X-ray diffractometer. MnO2 effectively suppress the diffusion of polysulfides and add a mechanical strength to the electrode. PEG binds the MnO2 and S, resulting in the minimization of active material loss and improves the electrochemical performance in lithium sulfur batteries. The PEG/MnO2/Sulfur composite exhibits discharge capacity of 647 mAh/g even after 30 cycles with appreciable sustainability. Therefore, the resulting PEG/MnO2/Sulfur composite exhibited as a desirable cathode material for Li-S battery.

Effect of Dispersoid on Sulfonium Ionic Liquid Based Gel Polymer Electrolyte for Lithium Secondary Battery.

The present study emphases on the effect of toting of TiO2 filler on the electrochemical enactment of polymer electrolyte containing PVdF-co-HFP(30) + SEt3TFSI(10) + EC/PC(60) + TiO2(x) wt% (Poly (vinylidene fluoride-co-hexafluoropropylene + Triethylsulfoniumbis(trifluoromethylsulfonyl)imide + Ethylene carbonate/Propylene carbonate (1:1 ratio) + Titanium dioxide) for lithium battery applications. Composite electrolytes with different weight percentages of TiO2 were prepared and characterized by different surface analytical, thermal and electrochemical techniques. With gradual increase of the amount of TiO2 upto 6 wt%, broadening of the prominent peak has been noted, suggesting a decrease in the degree of crystallinity upon the addition of TiO2, as revealed by X-ray diffraction (XRD). Raman and FT-IR studies confirm the presence of various functional groups, present in the matrix. The electrolyte with TiO2 (6 wt%) has maximum stability of 460 °C, as confirmed by thermal analysis. Conductivity of the composite polymer electrolytes increases upto 6 wt% of TiO2 (3.42 × 10-3 S/cm at 303 K) and further addition, causes a dip down in conductivity, indicating an improvement in the ionic conductivity and thermal stability with the incorporation of TiO2 filler. Surface morphologic images show the presence of surface and cavity in the polymer matrix, filled with the filler uniformly. Voltammetric studies confirm the electrochemical stability of films upto 4.62 V. Coin cell containing Li anode and LiFePO4 cathode along with polymer electrolyte/6 wt% TiO2 filler, delivers a first discharge capacity of 145 mAh/g with the working voltage of 3.4 V.

Structural and Morphological Studies on Li2Fe0.5Mn0.5SiO4/C Composite Synthesized Using Polyvinyl Alcohol for Energy Storage Devices.

In this study, we first focus on effects of PVA surfactant on Li2Fe0.5Mn0.5SiO4/C by using X-ray diffraction, Fourier transform infrared spectroscopy, micro Raman analysis, scanning electron microscope, transmission electron microscope and magnetization measurements. XRD result reveals the formation of new phase (Li2Fe0.5Mn0.5SiO4/C), as a result of embedded carbon, intensity of the peaks was also suppressed. Intensity domination of G-band in micro Raman analysis affirmed that the establishment of graphene formation which was yielded from decomposition of organic materials of both PVA and acetate. Confirmation of Si-O and Si-C bond in the as-prepared material was made by FTIR analyses. A well uniform spherical shaped morphology was observed in both SEM and TEM images. In addition, the TEM picture further demonstrates Li2Fe0.5Mn0.5SiO4/C with average particle size of about 20 nm by PVA introducing.

Facile Synthesis and Characterization of ZrO2 Nanoparticles via Modified Co-Precipitation Method.

The crystalline Zirconium oxide (ZrO2) nano particles were synthesized using optimized content of Zirconium nitrate (Zr(NO3)2·3H2O) with varying KOH concentration (0.5, 1 and 1.5 M) by co-precipitation method. The thermal history of the precursor was carefully analyzed through Thermogravimetric (TG/DTA) measurement. The as prepared samples were characterized to ensure structural, functional, morphological, compositional, chemical composition and band gap by X-ray diffractometer (XRD), Fourier transform infrared spectroscopy (FTIR), Laser Raman, scanning electron microscopy (SEM), High resolution Transverse Electron Microscopy (HR-TEM), X-ray photo electron spectroscopy (XPS), EDX, Photo luminescence spectroscopy (PL). The monoclinic structure with space group P21/c has been confirmed from XRD (JCPDS 89-9066). The Zr-O stretching vibration and Zr-O2-Zr bending vibrations were confirmed through FTIR analysis. The well dispersed particles with spherical morphology were confirmed through SEM and TEM analysis. The oxidation states of Zr, O and C were confirmed through XPS analysis. The oxygen vacancies and band gap of the particles were investigated through PL analysis.