Room Temperature Dielectric Characteristics of Chitosan-Graphene Films Embedded In Cellulose Fabric

MRS Advances ◽  
2018 ◽  
Vol 3 (1-2) ◽  
pp. 85-90
Author(s):  
Radha Perumal Ramasamy ◽  
Swathi Somanathan ◽  
Vinod K. Aswal ◽  
Miriam H. Rafailovich
Keyword(s):  
Dielectric Constant ◽  
Room Temperature ◽  
Heat Dissipation ◽  
Chitosan Film ◽  
Chitosan Solution ◽  
Dissipation Factor ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Cellulose Fabric ◽  
Chitosan Powder

ABSTRACTDevelopment of solid polymer electrolytes has potential applications for battery technology. Membranes should be environment friendly and also have high conductivity. We use chitosan, cellulose and graphene in this research. In this work, 1% (w/v) of chitosan powder and 1.5% (w/v) of acetic acid were dissolved in double distilled water. The solution was heated to 60°C under constant stirring until the chitosan powder was completely dissolved and a semi-transparent thick chitosan solution was obtained. To this chitosan solution, appropriate amounts of graphene (grade H5-XG Sciences) was added to have 5, 10, 20 and 30% graphene (weight with respect to chitosan). The solution was sonicated for dispersing graphene and then 100ml of it was poured on plastic dishes with and without cellulose fabric in it. The films were dried by slow evaporation technique. The sample thickness varied from 200 to 300µm. SEM images showed that chitosan film formed on cellulose and had grid like structures. Chitosan deposited more on the fibres of the cellulose. This is attributed to the rectangle shaped micro pores of cellulose fabric. From the cross section of the films, it was observed that graphene arranged in stacks along the plane of the cellulose fabric and the fabric became darker as graphene concentration increased. The dielectric properties such as dielectric constant, impedance, conductivity and dissipation factor were measured from 102 - 106 Hz. The conductivity of the sample increased as the frequency increased. The conductivity of the samples at room temperature increased with increase in graphene concentrations. The conductivity varied from 10-8 to 10-5 S/Cm as the graphene concentration increases from 0 to 30%. Hence conductivity increases significantly as graphene concentration increases. From the dissipation factor for the films, the relaxation process could be observed in the frequency ranging from 102 to 105 Hz. It is observed that as frequency increases, the relaxation tend to shift towards higher frequency indicating that graphene affects the relaxation of the polymer nanocomposite. At high frequency (106Hz) dissipation factor for cellulose fabric, chitosan in cellulose, chitosan with 5% graphene in cellulose, chitosan with 10% graphene in cellulose, chitosan with 20% graphene in cellulose, chitosan with 30% graphene in cellulose are 0.14, 0.19, 0.4, 0.8 and 1.38 respectively. This shows that dissipation factor increases as the graphene concentration increases. This implies that graphene improves heat dissipation in these films. The dielectric constant was observed to be maximum for chitosan with 30% graphene in cellulose indicating that the graphene may assemble into percolation networks at higher concentrations of graphene (20 and 30%).

scholarly journals Dielectric properties and conductivity of PVdF-co-HFP/LiClO4 polymer electrolytes

2018 ◽  
Vol 96 (7) ◽  
pp. 786-791 ◽  
Author(s):  
Kemal Ulutaş ◽  
Ugur Yahsi ◽  
Hüseyin Deligöz ◽  
Cumali Tav ◽  
Serpil Yılmaztürk ◽  
...  
Keyword(s):  
Dielectric Constant ◽  
Dielectric Properties ◽  
Dielectric Loss ◽  
Polymer Electrolytes ◽  
Room Temperature ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
Maximum Conductivity

In this study, it was aimed to prepare a series of PVdF-co-HFP based electrolytes with different LiClO4 loadings and to investigate their chemical and electrical properties in detail. For this purpose, PVdF-co-HFP based electrolytes with different LiClO4 loadings (1–20 weight %) were prepared using solution casting method. X-ray diffraction (XRD), differential scanning calorimetry, and thermogravimetric (TGA) –differential thermal and dielectric spectroscopy analysis of PVdF-co-HFP/LiClO4 were performed to characterize their structural, thermal, and dielectric properties, respectively. XRD results showed that the diffraction peaks of PVdF-co-HFP/LiClO4 electrolytes broadened and decreased with LiClO4. TGA patterns exhibited that PVdF-co-HFP/LiClO4 electrolytes with 20 wt % of LiClO4 had the lowest thermal stability and it degraded above 473 K, which is highly applicable for solid polymer electrolytes. Dielectric constant, dielectric loss, and conductivities were calculated by measuring capacitance and dielectric loss factor of PVdF-co-HFP/LiClO4 in the range from 10 mHz to 20 MHz frequencies at room temperature. In consequence, conductivities of PVdF-co-HFP/LiClO4 increased significantly with frequency for low loading of LiClO4 while they only slightly changed with higher LiClO4 addition. On the other hand, dielectric constant values of PVdF-co-HFP/LiClO4 films decreased with frequency whereas they rose with LiClO4 addition. The dielectric studies showed an increase in dielectric constant and dielectric loss with decreasing frequency. This result was attributed to high contribution of charge accumulation at the electrode–electrolyte interface. The electrolyte showed the maximum conductivity of 8 × 10−2 S/cm at room temperature.

Conductivity and Dielectric Analysis of Cellulose Based Solid Polymer Electrolytes Doped with Ammonium Carbonate (NH4CO3)

2015 ◽  
Vol 719-720 ◽  
pp. 67-72 ◽  
Author(s):  
M.I.H. Sohaimy ◽  
Mohd Ikmar Nizam Isa
Keyword(s):  
Dielectric Constant ◽  
Polymer Electrolytes ◽  
Room Temperature ◽  
Ammonium Carbonate ◽  
Dielectric Behavior ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Dielectric Analysis ◽  
Solution Cast ◽  
Cast Technique

The present work investigated the effect of carboxy methylcellulose (CMC) solid polymer electrolytes doped with ammonium carbonate (AC) prepared from solution cast technique. The CMC-AC solid polymer electrolytes system has been analyzed using EIS to understand its conductivity and dielectric behavior at temperature range of 303 K to 363 K. The highest conductivity achieved at room temperature (303K) is 7.71 x 10-6S cm-1doped with 7wt.% of AC and all samples follows Arrhenius behaviour. The dielectric constant (εr) value was found to be dependent of ionic dopant.

scholarly journals Electrical Conduction Mechanism in Solid Polymer Electrolytes: New Concepts to Arrhenius Equation

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Shujahadeen B. Aziz ◽  
Zul Hazrin Z. Abidin
Keyword(s):  
Dielectric Constant ◽  
Polymer Electrolytes ◽  
Conduction Mechanism ◽  
Dc Conductivity ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Arrhenius Behavior ◽  
Different Temperatures ◽  
Solution Cast ◽  
The Fourier Transform

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 (σdc(T,ε′)=σ0e−Ea/KBT) is also demonstrated.

A Lithiated Organic Nanofiber-Reinforced Composite Polymer Electrolyte Enabling Li-ion Conduction Highways for Solid-State Lithium Metal Batteries

2021 ◽  
Author(s):  
Liying Tian ◽  
Ying Liu ◽  
Zhe Su ◽  
Yu Cao ◽  
Wanyu Zhang ◽  
...  
Keyword(s):  
Solid State ◽  
Room Temperature ◽  
Low Cost ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Composite Polymer Electrolyte ◽  
Lithium Metal ◽  
Lithium Metal Batteries ◽  
Reinforced Composite ◽  
Li Ion

Solid polymer electrolytes (SPEs) with good flexibility and low cost are very promising for all-solid-state lithium metal batteries, but they suffer from the trad-off between ionic conductivity at room temperature...

scholarly journals The effects of additive on microstructure and electrical properties of batio3 ceramics

2004 ◽  
Vol 1 (3) ◽  
pp. 89-98 ◽  
Author(s):  
Vesna Paunovic ◽  
Ljiljana Zivkovic ◽  
Ljubomir Vracar ◽  
Vojislav Mitic ◽  
Miroslav Miljkovic
Keyword(s):  
Dielectric Constant ◽  
Curie Temperature ◽  
Room Temperature ◽  
Low Frequency ◽  
Dissipation Factor ◽  
The Other ◽  
Uniform Microstructure ◽  
Average Grain Size ◽  
Solid State Sintering ◽  
Curie Temperatures

In this paper comparative investigations of microstructure and dielectric properties of BaTiO3 ceramics doped with 1.0 wt% of Nb2O5, MnCO3 and CaZrO3 have been done. BaTiO3 samples were prepared using conventional method of solid state sintering at 13000C for two hours. Two distinguish micro structural regions can be observed in sample doped with Nb2O5. The first one, with a very small grained microstructure and the other one, with a rod like grains. In MnCO3 and CaZrO3 doped ceramics the uniform microstructure is formed with average grain size about 0.5- 2?m and 3-5?m respectively. The highest value of dielectric permittivity at room temperature and the greatest change of permittivity in function of temperature were observed in MnCO3/BaTiO3. In all investigated samples dielectric constant after initially large value at low frequency attains a constant value at f = 6kHz. A dissipation factor is independent of frequency greater than 10 kHz and, depending of systems, lies in the range from 0.035 to 0.25. At temperatures above Curie temperatures, the permittivity of all investigated samples follows a Curie- Weiss law. A slight shift of Curie temperature to the lower temperatures, in respect of Curie temperature for undoped BaTiO3, was observed in all investigated samples.

scholarly journals Contribution Succinonitrile additive for Performa LiTFSi Solid Polymer Electrolytes for Li-Ion Battery

2020 ◽  
Vol 20 (2) ◽  
Author(s):  
Qolby Sabrina ◽  
Titik Lestariningsih ◽  
Christin Rina Ratri ◽  
Achmad Subhan
Keyword(s):  
Ionic Conductivity ◽  
Polymer Electrolytes ◽  
Room Temperature ◽  
Lithium Salt ◽  
Ionic Conduction ◽  
Lithium Ion ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Half Cell ◽  
Li Ion

Solid polymer electrolyte (SPE) appropriate to solve packaging leakage and expansion volume in lithium-ion battery systems. Evaluation of electrochemical performance of SPE consisted of mixture lithium salt, solid plasticizer, and polymer precursor with different ratio. Impedance spectroscopy was used to investigate ionic conduction and dielectric response lithium bis(trifluoromethane)sulfony imide (LiTFSI) salt, and additive succinonitrile (SCN) plasticizer. The result showing enhanced high ionic conductivity. In half-cell configurations, wide electrochemical stability window of the SPE has been tested. Have stability window at room temperature, indicating great potential of SPE for application in lithium ion batteries. Additive SCN contribute to forming pores that make it easier for the li ion to move from the anode to the cathode and vice versa for better perform SPE. Pore of SPE has been charaterization with FE-SEM. Additive 5% w.t SCN shows the best ionic conductivity with 4.2 volt wide stability window and pretty much invisible pores.

Polymer-in-salt solid electrolytes for lithium-ion batteries

2019 ◽  
Vol 12 (06) ◽  
pp. 1930006 ◽  
Author(s):  
Chengjun Yi ◽  
Wenyi Liu ◽  
Linpo Li ◽  
Haoyang Dong ◽  
Jinping Liu
Keyword(s):  
Ionic Conductivity ◽  
Lithium Ion Batteries ◽  
Smart Grids ◽  
Solid Electrolytes ◽  
Room Temperature ◽  
Lithium Salt ◽  
Lithium Ion ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Polymer Lithium Ion Batteries

Solid-state polymer lithium-ion batteries with better safety and higher energy density are one of the most promising batteries, which are expected to power future electric vehicles and smart grids. However, the low ionic conductivity at room temperature of solid polymer electrolytes (SPEs) decelerates the entry of such batteries into the market. Creating polymer-in-salt solid electrolytes (PISSEs) where the lithium salt contents exceed 50[Formula: see text]wt.% is a viable technology to enhance ionic conductivity at room temperature of SPEs, which is also suitable for scalable production. In this review, we first clarify the structure and ionic conductivity mechanism of PISSEs by analyzing the interactions between lithium salt and polymer matrix. Then, the recent advances on polyacrylonitrile (PAN)-based PISSEs and polycarbonate derivative-based PISSEs will be reviewed. Finally, we propose possible directions and opportunities to accelerate the commercializing of PISSEs for solid polymer Li-ion batteries.

scholarly journals Ion-Locking in Solid Polymer Electrolytes for Reconfigurable Gateless Lateral Graphene p-n Junctions

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1089 ◽  
Author(s):  
Jierui Liang ◽  
Ke Xu ◽  
Swati Arora ◽  
Jennifer E. Laaser ◽  
Susan K. Fullerton-Shirey
Keyword(s):  
Polymer Electrolytes ◽  
Room Temperature ◽  
Thermal Quenching ◽  
Logic Circuits ◽  
Solid Polymer Electrolytes ◽  
Solid Polymer ◽  
Double Layers ◽  
Potential Applications ◽  
Thermally Triggered ◽  
Room Temperature Operation

A gateless lateral p-n junction with reconfigurability is demonstrated on graphene by ion-locking using solid polymer electrolytes. Ions in the electrolytes are used to configure electric-double-layers (EDLs) that induce p- and n-type regions in graphene. These EDLs are locked in place by two different electrolytes with distinct mechanisms: (1) a polyethylene oxide (PEO)-based electrolyte, PEO:CsClO4, is locked by thermal quenching (i.e., operating temperature < Tg (glass transition temperature)), and (2) a custom-synthesized, doubly-polymerizable ionic liquid (DPIL) is locked by thermally triggered polymerization that enables room temperature operation. Both approaches are gateless because only the source/drain terminals are required to create the junction, and both show two current minima in the backgated transfer measurements, which is a signature of a graphene p-n junction. The PEO:CsClO4 gated p-n junction is reconfigured to n-p by resetting the device at room temperature, reprogramming, and cooling to T < Tg. These results show an alternate approach to locking EDLs on 2D devices and suggest a path forward to reconfigurable, gateless lateral p-n junctions with potential applications in polymorphic logic circuits.

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