scholarly journals Synthesis of Polyaniline-Cellulose Conductive Composites with Modified Initial Treatment of Cellulose

2020 ◽  
Vol 1 (1) ◽  
pp. 18
Author(s):  
Berlian Sitorus ◽  
Ferdinand Hidayat ◽  
Veinardi Suendo
Keyword(s):  
Initial Treatment ◽  
Electrochemical Impedance ◽  
Conductive Polymers ◽  
Environmental Stability ◽  
Infrared Spectrometry ◽  
X Ray Diffraction ◽  
Conductive Composites ◽  
Cellulose Composites ◽  
Diffraction Patterns ◽  
Polyaniline Composites

Conductive polymers are polymers that can conduct electric current because they have conjugated double bonds. Polyaniline is one example of conductive polymers with advantages such as high conductivity, excellent environmental stability, and easy to be synthesized. Nevertheless, polyaniline still has disadvantages such as rigid physical properties that can limit its usage application. Some studies state that stiffness can be overcome by forming composites. Cellulose has been used as a matrix in making polyaniline composites because of its flexible nature. In this study, the synthesis of PANI-cellulose composites was carried out with five different treatment variations, including swelling pretreatment and without swelling pretreatment, reaction through sonication, and without sonication. This treatment difference aims to examine the effect of swelling and sonication processes on composite properties analyzed through peaks appear in Fourier Transformation Infrared spectrometry, conductivity using Electrochemical Impedance Spectroscopy, as well as differences in the diffractogram of X-Ray Diffraction. In addition to the variations in the initial treatment, variations in the mass of the aniline were also used. The aim is to determine the optimum amount of aniline used to obtain a composite with the highest conductivity value. Inserting aniline to cellulose to synthesis PANI-cellulose composites affected the absorption peaks at wave numbers that identify C-N bonds in PANI-cellulose composites. Also, there are typical peaks of C-N indicated the formation of hydrogen bonds in the composite between PANI and cellulose. Analysis with EIS shows that composite C with an aniline concentration of 2.0 g/L has the highest conductivity, which is 4.77 x 10-6 S/cm. The diffractograms show the formation of organic compounds on PANI-cellulose composites, marked by the peak intensity and widen diffraction patterns.

scholarly journals Electrochemical Behavior of NH4F-Pretreated Li1.25Ni0.20Fe0.13Co0.33Mn0.33O2 Cathodes for Lithium-ion Batteries

2020 ◽  
Vol 10 (3) ◽  
pp. 1021
Author(s):  
Yonglei Zheng ◽  
Yikai Li ◽  
He Wang ◽  
Siheng Chen ◽  
Xiangxin Guo ◽  
...  
Keyword(s):  
Lithium Ion Batteries ◽  
Electrochemical Impedance ◽  
Lithium Ion ◽  
X Ray Diffraction ◽  
Capacity Retention ◽  
Hierarchical Microspheres ◽  
Electrochemical Cycling ◽  
Novel Method ◽  
Diffraction Patterns ◽  
Discharge Capacities

We report a novel method to fabricate lithium-ion batteries cathodes with the NH4F pretreatment. In this study, NH4F-pretreated Li1.25Ni0.20Fe0.13Co0.33Mn0.33O2 hollow nano-micro hierarchical microspheres were synthesized for use as cathode materials. The X-ray diffraction patterns of NH4F-pretreated Li1.25Ni0.20Co0.33Fe0.13Mn0.33O2 were analyzed with the RIETAN-FP software program, and the results showed that the samples possess a layered α-NaFeO2 structure. The effects of pretreatment with NH4F on the electrochemical performance of the pristine material were evaluated through charge/discharge cycling, the rate performance, and electrochemical impedance spectroscopy (EIS). Pretreatment with NH4F significantly improved the discharge capacities and coulombic efficiencies of Li1.25Ni0.20Co0.33Fe0.13Mn0.33O2 in the first cycle and during subsequent electrochemical cycling. The sample pretreated with an appropriate amount of NH4F (NFCM 90) showed the highest discharge capacity (209.1 mA h g−1) and capacity retention (85.2% for 50 cycles at 0.1 C). The EIS results showed that the resistance of the NFCM 90 sample (76.32 Ω) is lower than that of the pristine one (206.2 Ω).

Preparation of Cu2ZnSnS4 Thin Films by Successive Ionic Layer Adsorption and Reaction (SILAR) Method for Supercapacitor Applications

2020 ◽  
Vol 20 (10) ◽  
pp. 6235-6244 ◽  
Author(s):  
A. Murugan ◽  
V. Siva ◽  
A. Shameem ◽  
S. Asath Bahadur
Keyword(s):  
Thin Films ◽  
Electrochemical Behavior ◽  
Electrochemical Impedance ◽  
X Ray Diffraction ◽  
Silar Method ◽  
Layer Adsorption ◽  
Diffraction Patterns ◽  
Czts Thin Films ◽  
Supercapacitor Applications ◽  
Ionic Layer

The Cu2ZnSnS4 (CZTS) thin films have been prepared at different deposition cycles, deposited on a glass substrate by successive ionic layer adsorption and reaction (SILAR) method followed by the annealing process at elevated temperature. The investigations on the films have been carried out to understand and confirm its structure, functional group present, crystalline morphology, optical and electrochemical behavior. The powder X-ray diffraction patterns recorded indicate that the deposited films are formed in the tetragonal structure. Other parameters like grain size, dislocation density, and microstrain are also calculated. The uniform surface of the films with spherical shaped morphology has been observed by Scanning Electron Microscopy, and the elemental compositions have been confirmed by EDAX. Electrochemical behavior such as cyclic voltammetry, electrochemical impedance spectroscopy and galvanostatic charge–discharge analysis have been carried out by electrochemical workstation. The modified electrode exhibits maximum specific capacitance value as 416 F/g for a pure sample. Optical studies have shown that the band gaps are estimated between 1.40 eV and 1.57 eV.

Simultaneous improvement of mechanical and conductive properties of poly(amide-imide) composites using carbon nano-materials with different morphologies

2020 ◽  
Vol 40 (10) ◽  
pp. 806-814 ◽  
Author(s):  
Yawen Fang ◽  
Huang Yu ◽  
Yanbin Wang ◽  
Zhehao Zhang ◽  
Changlong Zhuang ◽  
...  
Keyword(s):  
Polymer Composites ◽  
Electron Flow ◽  
Conductive Polymer ◽  
Infrared Spectrometry ◽  
Nano Materials ◽  
X Ray Diffraction ◽  
Conductive Composites ◽  
Multi Walled Carbon Nanotubes ◽  
Conductive Properties ◽  
Walled Carbon Nanotubes

AbstractTwo conductive carbon materials, one with a beaded-like structure (carbon black, ECP) and another with tube-like structure (functionalized multi-walled carbon nanotubes, FMWCNTs), were added into a poly(amide-imide) (PAI) matrix. Combining the advantages of ECP (good compatibility) and FMWCNT (high conductivity), the conductivity was improved from 3.7 S m−1 for PAI/FMWCNT polymer composites to 100 S m−1 for PAI/FMWCNT/ECP ternary conductive polymer composites, much higher than that of the sum of PAI/ECP and PAI/FMWCNT. The tensile strength increased from 40 to 70 MPa. The improved conductive and mechanical properties were mainly due to much more intensive conductive network produced in the PAI/FMWCNT/ECP ternary composites, which is useful for electron flow and stress spread. The number of hydrogen bond was increased by adding ECP into PAI/FMWCNT binary composites, and played an important role in forming the unique morphology as evident by Fourier transform infrared spectrometry (FTIR) and X-ray diffraction (XRD) measurements. These conductive composites have potential for flexible electronic applications.

Crystallization behavior of polypropylene/silver nanocomposites using polyethylene glycol as reducing agent and interface modifier

2015 ◽  
Vol 30 (5) ◽  
pp. 662-677 ◽  
Author(s):  
Pablo H Camacho ◽  
Ana B Morales-Cepeda ◽  
Homero Salas-Papayanopolos ◽  
Jesús E Bautista ◽  
Carlos Castro ◽  
...  
Keyword(s):  
Polyethylene Glycol ◽  
Reducing Agent ◽  
Infrared Spectrometry ◽  
X Ray Diffraction ◽  
Ag Nps ◽  
Scanning Calorimetry ◽  
Easy Method ◽  
Β Phase ◽  
Single Screw Extruder ◽  
Diffraction Patterns

In this work, isotactic polypropylene (iPP) nanocomposites were prepared containing silver nanoparticles (Ag-NPs) with a novel and easy method, using polyethylene glycol (PEG) as reducing agent and surface modifier. Ag-NPs were prepared using different amounts in weight of silver nitrate into PEG to induce the formation of Ag-NPs. PP/Ag nano compounds were prepared by melt blend method: single-screw extruder and internal Brabender mixer. The effects of Ag-NPs and PEG on the crystallization, morphology, thermal, and mechanical properties were evaluated. Ag-NPs with a particle size of 80 nm and typical growth of the β-form in iPP were observed. The presence of PEG in samples of PP/Ag-NPs was detected by infrared spectrometry and the peak characteristic of Ag-NPs by ultraviolet–visible analysis. X-Ray diffraction patterns and differential scanning calorimetry thermograms showed the β-phase formation in both of the dispersion methods, but Brabender mixer showed higher percentages of crystallinity (31% of β-phase). The elongation at break was increased and it was directly dependent on the relative amount of crystalline β-phase. PEG is an excellent precursor to get Ag-NPs and a good interface modifier of iPP.

scholarly journals Improvement of La0.8Sr0.2MnO3−δ Cathode Material for Solid Oxide Fuel Cells by Addition of YFe0.5Co0.5O3

Materials ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 642
Author(s):  
Michał Mosiałek ◽  
Małgorzata Zimowska ◽  
Dzmitry Kharytonau ◽  
Anna Komenda ◽  
Miłosz Górski ◽  
...  
Keyword(s):  
Fuel Cells ◽  
Solid Oxide Fuel Cells ◽  
Polarization Resistance ◽  
High Efficiency ◽  
Electrochemical Impedance ◽  
Solid Oxide ◽  
Oxide Fuel ◽  
X Ray Diffraction ◽  
Composite Cathodes ◽  
Diffraction Patterns

The high efficiency of solid oxide fuel cells with La0.8Sr0.2MnO3−δ (LSM) cathodes working in the range of 800–1000 °C, rapidly decreases below 800 °C. The goal of this study is to improve the properties of LSM cathodes working in the range of 500–800 °C by the addition of YFe0.5Co0.5O3 (YFC). Monophasic YFC is synthesized and sintered at 950 °C. Composite cathodes are prepared on Ce0.8Sm0.2O1.9 electrolyte disks using pastes containing YFC and LSM powders mixed in 0:1, 1:19, and 1:1 weight ratios denoted LSM, LSM1, and LSM1, respectively. X-ray diffraction patterns of tested composites reveal the presence of pure perovskite phases in samples sintered at 950 °C and the presence of Sr4Fe4O11, YMnO3, and La0.775Sr0.225MnO3.047 phases in samples sintered at 1100 °C. Electrochemical impedance spectroscopy reveals that polarization resistance increases from LSM1, by LSM, to LSM2. Differences in polarization resistance increase with decreasing operating temperatures because activation energy rises in the same order and equals to 1.33, 1.34, and 1.58 eV for LSM1, LSM, and LSM2, respectively. The lower polarization resistance of LSM1 electrodes is caused by the lower resistance associated with the charge transfer process.

Use of Selective Sorbents for Liquid Wastes Treatment

1997 ◽  
Vol 506 ◽  
Author(s):  
I.M. El-Naggar ◽  
N. Belacy ◽  
M.M. Abou-Mesalam ◽  
H.F. Aly
Keyword(s):  
Citric Acid ◽  
Liquid Waste ◽  
Distribution Coefficients ◽  
Infrared Spectrometry ◽  
Ferric Nitrate ◽  
X Ray Diffraction ◽  
Radioactive Liquid Waste ◽  
Acid Media ◽  
Quantitative Separation ◽  
Diffraction Patterns

ABSTRACTAcidic salts of polyvalent metal antimonates(M-antimonates(M-Sb); M=Cerium, Tin, Titanium and Silicon) have been synthesized under different conditions( 1,2). The products were characterized by powdered X-ray diffraction patterns, Differential Thermal Analysis(DTA) and infrared spectrometry. Chemical stability of the product materials were studied by mixing 50 mg of the prepared materials with 50 ml of the desired medium(H20, HNO3 and HCI) with determination for the concentration of the metalions dissolved(Sb, Ce, Sn, Ti and Si) which showed high chemical stabilities in water and acid media up to I OM HNO 3 and 6M HCI.The data of the distribution coefficients showed that the selectivity decrease in the order; Eu3+> Co2+> Sr2+> Cs+ for cerium(IV) antimonate(CeSb), tin(IV) antimonate(SnSb) and silicon(IV) antimonate(SiSb), while the selectivity decrease in the order UO22+>Th4+ for titanium(IV) antimonate(TiSb). Besides, the effect of EDTA, citric acid, ferric nitrate and sodium nitrate as interfering ions in solution on the distribution coefficient of the studied cations for CeSb and SnSb were studied under certain conditions. The results showed that, the Kj values of CS+, Co2+ and Eu3+ are decreases with increasing the concentrations of ferric and sodium nitrates in the feed solutions for both materials and also Kd values are effected to some extent in case of EDTA and citric acid. Based on the obtained results, practical separation experiments on column were performed(3).The following figures represents the break-through curves for CeSb and SnSb columns for some radionuclides 60Co (10-3M ) as example. From the above studies we conclude that, CeSb and SnSb have been successfully used for the quantitative separation of cesium which suggests its use in the treatment of radioactive liquid waste.

Evaluation of Freezing Methods by Low Temperature X-Ray Diffraction

1977 ◽  
Vol 35 ◽  
pp. 330-333
Author(s):  
T. Gulik-Krzywicki ◽  
M.J. Costello
Keyword(s):  
Biological Materials ◽  
Molecular Organization ◽  
X Ray Diffraction ◽  
Glass Capillary ◽  
X Ray ◽  
Rate Dependent ◽  
Before And After ◽  
Freeze Etching ◽  
Diffraction Patterns ◽  
Set Up

Freeze-etching electron microscopy is currently one of the best methods for studying molecular organization of biological materials. Its application, however, is still limited by our imprecise knowledge about the perturbations of the original organization which may occur during quenching and fracturing of the samples and during the replication of fractured surfaces. Although it is well known that the preservation of the molecular organization of biological materials is critically dependent on the rate of freezing of the samples, little information is presently available concerning the nature and the extent of freezing-rate dependent perturbations of the original organizations. In order to obtain this information, we have developed a method based on the comparison of x-ray diffraction patterns of samples before and after freezing, prior to fracturing and replication.Our experimental set-up is shown in Fig. 1. The sample to be quenched is placed on its holder which is then mounted on a small metal holder (O) fixed on a glass capillary (p), whose position is controlled by a micromanipulator.

Examination of Rabbit Fc Crystals

1968 ◽  
Vol 26 ◽  
pp. 140-141
Author(s):  
J. P. Robinson ◽  
P. G. Lenhert
Keyword(s):  
Molecular Weight ◽  
Flat Plate ◽  
Phosphate Buffer ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Neutral Ph ◽  
Small Crystals ◽  
Carbon Coated ◽  
Diffraction Patterns

Crystallographic studies of rabbit Fc using X-ray diffraction patterns were recently reported. The unit cell constants were reported to be a = 69. 2 A°, b = 73. 1 A°, c = 60. 6 A°, B = 104° 30', space group P21, monoclinic, volume of asymmetric unit V = 148, 000 A°3. The molecular weight of the fragment was determined to be 55, 000 ± 2000 which is in agreement with earlier determinations by other methods.Fc crystals were formed in water or dilute phosphate buffer at neutral pH. The resulting crystal was a flat plate as previously described. Preparations of small crystals were negatively stained by mixing the suspension with equal volumes of 2% silicotungstate at neutral pH. A drop of the mixture was placed on a carbon coated grid and allowed to stand for a few minutes. The excess liquid was removed and the grid was immediately put in the microscope.

Quantitative Electron Microscope with imaging plate

1994 ◽  
Vol 52 ◽  
pp. 408-409
Author(s):  
D. Shindo
Keyword(s):  
Electron Microscope ◽  
Dynamic Range ◽  
Processing System ◽  
Digital Data ◽  
Imaging Plate ◽  
Crystal Thickness ◽  
X Ray Diffraction ◽  
Resolution Electron ◽  
Electron Intensity ◽  
Diffraction Patterns

Imaging plate has good properties, i.e., a wide dynamic range and good linearity for the electron intensity. Thus the digital data (2048x1536 pixels, 4096 gray levels in log scale) obtained with the imaging plate can be used for quantification in electron microscopy. By using the image processing system (PIXsysTEM) combined with a main frame (ACOS3900), quantitative analysis of electron diffraction patterns and high-resolution electron microscope (HREM) images has been successfully carried out.In the analysis of HREM images observed with the imaging plate, quantitative comparison between observed intensity and calculated intensity can be carried out by taking into account the experimental parameters such as crystal thickness and defocus value. An example of HREM images of quenched Tl2Ba2Cu1Oy (Tc = 70K) observed with the imaging plate is shown in Figs. 1(b) - (d) comparing with a structure model proposed by x-ray diffraction study of Fig. 1 (a). The image was observed with a JEM-4000EX electron microscope (Cs =1.0 mm).

On the Properties of an Ion Conductive System Incorporated in Hybrid Films

2000 ◽  
Vol 628 ◽  
Author(s):  
G. González ◽  
P. J. Retuert ◽  
S. Fuentes
Keyword(s):  
Electrochemical Impedance ◽  
Ternary Phase Diagram ◽  
Lithium Perchlorate ◽  
Molar Ratio ◽  
Ionic Conductors ◽  
X Ray Diffraction ◽  
Poly Ethylene Oxide ◽  
Ion Conducting ◽  
Poly Ethylene ◽  
High Degree

ABSTRACTBlending the biopolymer chitosan (CHI) with poly (aminopropilsiloxane) oligomers (pAPS), and poly (ethylene oxide) (PEO) in the presence of lithium perchlorate lead to ion conducting products whose conductivity depends on the composition of the mixture. A ternary phase diagram for mixtures containing 0.2 M LiClO4 shows a zone in which the physical properties of the products - transparent, flexible, mechanically robust films - indicate a high degree of molecular compatibilization of the components. Comparison of these films with binary CHI-pAPS nanocomposites as well as the microscopic aspect, thermal behavior, and X-ray diffraction pattern of the product with the composition PEO/CHI/pAPS/LiClO4 1:0.5:0.6:0.2 molar ratio indicates that these films may be described as a layered nanocomposite. In this composite, lithium species coordinated by PEO and pAPS should be inserted into chitosan layers. Electrochemical impedance spectroscopy measurements indicate the films are pure ionic conductors with a maximal bulk conductivity of 1.7*10-5 Scm-1 at 40 °C and a sample-electrode interface capacitance of about 1.2*10-9 F.

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