scholarly journals Studies on Synthesis, Characterization and Transport Properties of Ta2O5 Doped Polyaniline Composites

2021 ◽  
Vol 7 (1) ◽  
pp. 942-945
Author(s):  
Nagajyoti ◽  
Kalayne Sangshetty
Keyword(s):  
Structural Changes ◽  
Morphological Changes ◽  
Oxidative Polymerization ◽  
Average Crystallite Size ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Doped Polyaniline ◽  
Polyaniline Composites ◽  
Composite Samples

Polyaniline (PANI) and PANI/Ta2O5 composite samples were prepared using chemical oxidative polymerization technique in the presence of hydrochloric acid (HCl) at room temperature. The effect of Ta2O5 on surface morphology and structural changes have been investigated and evaluated by X-ray diffraction (XRD) and scanning electron microscope (SEM) techniques. The XRD pattern of the PANI and PANI/Ta2O5 confirm the formation of PANI and its composite. The average crystallite size of the PANI is 2.86 nm which is increased to 46.80 nm when Ta2O5 was doped in the PANI matrix. SEM micrographs of the composite confirm the morphological changes in the composite materials. In the electrical conductivity studies, ac conductivity was carried as function of frequency and dc conductivity was studied as a function of temperature. Further to describe the dielectric properties of the PANI and composite, dielectric constant and dielectric loss was studied as a function of frequency.

Spectroscopic and Electrical Studies of Ferrous Sulphate Doped Polyaniline

2012 ◽  
Vol 585 ◽  
pp. 224-227
Author(s):  
Anand Kumar ◽  
Ali Vazid ◽  
Sushil Kumar
Keyword(s):  
Polymer Composites ◽  
Structural Changes ◽  
Metal Salt ◽  
Potassium Dichromate ◽  
Ferrous Sulphate ◽  
Oxidative Polymerization ◽  
Dc Conductivity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Visible

Polyaniline (PANI) has been synthesized by chemical oxidative polymerization technique with potassium dichromate oxidant in aqueous hydrochloric acid medium. After polymerization, the polymer so prepared is doped with ferrous sulphate, a transition metal salt, with tetrahydrofuran and water as solvents. The undoped/doped samples were characterized by various techniques such as UV-visible spectroscopy, FTIR spectroscopy, X-ray diffraction and dc conductivity measurements. UV-visible absorption studies revealed the presence of cation/polaron transitions and the presence of direct optical transitions. FTIR studies provide information regarding structural changes in the backbone of PANI with doping concentration. X-ray diffraction patterns of powdered polymer composites showed amorphous nature as mostly conducting polymers exhibit. The dc conductivity of PANI-ferrous sulphate composites were measured by two probe method in pellet form at room temperature (300 K) and found to increase with temperature showing the semiconductor behavior of synthesized polymer composites

Synthesis and Properties of Conducting Polyaniline by Co-Doping with Sulfosalicylic Acid and Sulfate Acid

2010 ◽  
Vol 663-665 ◽  
pp. 481-485 ◽  
Author(s):  
Hui Huang ◽  
Zhong Cheng Guo ◽  
Ju Kang Li
Keyword(s):  
Fourier Transform ◽  
Oxidative Polymerization ◽  
X Ray Diffraction ◽  
Chemical Oxidative Polymerization ◽  
Sulfosalicylic Acid ◽  
X Ray ◽  
Co Doping ◽  
Doped Polyaniline ◽  
Fourier Transform Raman ◽  
Ft Raman

A chemical oxidative polymerization of aniline sulfosalicylic acid (ANISSA) and aniline sulfate acid (ANIH2SO4) was performed in an aqueous solution. A co-doped polyaniline (PANI) was thus obtained, a higher conductivity than the insoluble H2SO4-doped PANI compressed pellet, and much higher conductivity than that prepared from pure ANISSA. The PANI doped with SSA and H2SO4 was characterized using Fourier-transform infrared spectra (FTIR), Fourier-transform Raman spectra (FT-Raman), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The investigation reveals that SSA and H2SO4 as dopant not only enhances crystallinity of polyaniline but also stability of polyaniline.

scholarly journals Synthesis and Antibacterial Aspects of Graphitic C3N4@Polyaniline Composites

Coatings ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 950
Author(s):  
Mohammad Oves ◽  
Mohammad Omaish Ansari ◽  
Reem Darwesh ◽  
Afzal Hussian ◽  
Mohamed F. Alajmi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Morphological Analysis ◽  
Oxidative Polymerization ◽  
X Ray Diffraction ◽  
X Ray ◽  
E Coli ◽  
Transmission Electron ◽  
Aging Conditions ◽  
Polyaniline Composites

In this work, Pani and Pani@g-C3N4 was synthesized by in situ oxidative polymerization methodology of aniline, in the presence of g-C3N4. The as prepared Pani@g-C3N4 was characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction (XRD). The morphological analysis showed well dispersed Pani in g-C3N4, as well as the coating of Pani on g-C3N4. The XRD further revealed this, and peaks of Pani as well as g-C3N4 was observed, thereby suggesting successful synthesis of the composite. The DC electrical conductivity studies under isothermal and cyclic aging conditions showed high stability of composites over 100 °C. Further, the synthesized composite material proved to be an excellent antimicrobial agent against both type i.e., gram positive Streptococcus pneumoniae and negative bacteria Escherichia coli. In the zone inhibition assay 18 ± 0.5, 16 ± 0.75 and 20 ± 0.5, 22 ± 0.5 mm zone diameter were found against E. coli and S. pneumoniae in presence of pure g-C3N4 and Pani@g-C3N4 at 50 µg concentrations, respectively. Further antimicrobial activity in the presence of sunlight in aqueous medium showed that Pani@g-C3N4 is more potent than pure g-C3N4.

scholarly journals X-Ray Diffraction and Differential Scanning Calorimetry of BaTiO3/ Polyvinyl Chloride Nanocomposites

2015 ◽  
Vol 1 (10) ◽  
pp. 359
Author(s):  
Mohamed Yousef Farag El Zayat
Keyword(s):  
Differential Scanning Calorimetry ◽  
Polyvinyl Chloride ◽  
Structural Changes ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
The Core ◽  
Dsc Measurements ◽  
Scherrer Formula ◽  
Composite Samples

AbstractAiming to improve the inferior properties of polyvinyl chloride polymer, (BaTiO3)x(PVC)100-x composite samples were prepared and investigated. The structural changes of the composite (BaTiO3)x(PVC)100-x were studied as a function of BT content using FTIR, XRD and DSC measurements. Attention is paid to the tetragonality changes during composition changes.It was found that the hindrance to the PVC crystallization becomes less and less serious with the increase of BT ratio in the composite. This behavior could be attributed to the interaction between Ba+2 ions and Chlorine in the polymer. The FTIR spectra indicate a clear interaction between PVC and BaTiO3 particles as is concluded from XRD results.The Scherrer formula was used to estimate the grain size for the included BT in the (BT)x (PVC)100x composite samples. The composite samples show abnormally small tetragonality for its BT content less than unity (?/a < 1). It seems that in (BaTiO3)x(PVC)100-x composite samples, the stress that stabilized the tetragonal phase of the core regions of BT decreased, leading to lower tetragonality (c/a ratio). It seems that Tg of the composite samples increases with the increase of its BT content. Also DSC results reveal the increase of crystallization with the increase of BT content in the composite.

Preparation and Microstructure of Nanocomposite Mg-3Al-Zn Alloy by HDDR Combined with Ball Milling

2011 ◽  
Vol 264-265 ◽  
pp. 496-501
Author(s):  
Hong Fei Sun ◽  
Wa Fang ◽  
Zhen Xing Yu ◽  
Wen Bin Fang
Keyword(s):  
Ball Milling ◽  
Structural Changes ◽  
Average Crystallite Size ◽  
Hydrogen Atmosphere ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Milling In Hydrogen ◽  
Average Size ◽  
Zn Alloy

Nanocrystallite Mg-3Al-Zn alloy was synthesized by ball milling of elemental powders of Mg, Al and Zn under hydrogen atmosphere. The powders of Mg, Al and Zn were mechanical alloying and disproportionated by ball milling under hydrogen and desorption-recombination was then performed. The structural changes due to both the milling in hydrogen and the subsequent desorption-recombination treatment were characterized by X-ray diffraction (XRD). The desorption–recombination behavior of the hydrogenation alloy was investigated by differential scanning calorimetry (DSC). The morphology and microstructure of the final alloy powders subject to desorption–recombination treatment were observed by TEM and HRTEM, respectively. The results showed that, by milling in hydrogen for 60 h, the Mg-3Al-Zn alloy was disproportionated into nano-structured with average size of about 60-70 nm, and a subsequent desorption–recombination treatment at 320°C for 30 min alloy didn’t vary the average crystallite size of powders.

High Resolution Replication of Organoclay Surfaces

1982 ◽  
Vol 40 ◽  
pp. 576-577
Author(s):  
W. W. Barker ◽  
W. E. Rigsby ◽  
V. J. Hurst ◽  
W. J. Humphreys
Keyword(s):  
Clay Mineral ◽  
Organic Molecule ◽  
Organic Molecules ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Naturally Occurring ◽  
Silicate Layers ◽  
Mineral Identification

Experimental clay mineral-organic molecule complexes long have been known and some of them have been extensively studied by X-ray diffraction methods. The organic molecules are adsorbed onto the surfaces of the clay minerals, or intercalated between the silicate layers. Natural organo-clays also are widely recognized but generally have not been well characterized. Widely used techniques for clay mineral identification involve treatment of the sample with H2 O2 or other oxidant to destroy any associated organics. This generally simplifies and intensifies the XRD pattern of the clay residue, but helps little with the characterization of the original organoclay. Adequate techniques for the direct observation of synthetic and naturally occurring organoclays are yet to be developed.

Physico-Chemical and Morphological Changes of Sayong Kaolinite Clay Treated with Sulphuric Acid for Enzyme Immobilization

2013 ◽  
Vol 832 ◽  
pp. 589-595 ◽  
Author(s):  
N.A. Edama ◽  
A. Sulaiman ◽  
K.H. Ku Hamid ◽  
M.N. Muhd Rodhi ◽  
Mohibah Musa ◽  
...  
Keyword(s):  
Surface Area ◽  
Sulphuric Acid ◽  
Enzyme Immobilization ◽  
Morphological Changes ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
Kaolinite Clay ◽  
X Ray ◽  
Mineral Oxides ◽  
Physico Chemical

This study analyzed the effects of sulphuric acid (H2SO4) treatment on pysico-chemical properties and morphological changes of clay obtained from Sg. Sayong, Perak. The clay was ground and sieved to <150μm and treated with different concentrations of H2SO4. The treatment was completed by refluxing the clay with different concentration of H2SO4 (1M, 5M and 10M ) at 100 °C for 4 hours and followed by calcination at 500 °C for 1 hour. The physic-chemical properties and morphological changes of the untreated and treated clay were compared using Surface Area Analyser, X-Ray Diffraction (XRD), Field Emission Scanning Electron Micrograph (FESEM), X-Ray Diffraction (XRD) and Fourier Transformed Infrared Spectroscopy (FTIR). The results showed that acid treatment of 5M increased the surface area from 25 m2/g to 75 m2/g and the pore volume increased from 0.1518 cc/g to 0.3546 cc/g. The nanopore size of the clay decreased from 24.8 nm to 19.4 nm after treated with acid. This can be explained due to the elimination of the exchangeable cations and generation of microporosity. The results of XRF showed SiO2 increased from 58.34% to 74.52% and Al2O3 reduced from 34.6% to 18.31%. The mineral oxides such as Fe2O3, MgO, CaO, K2O and TiO2 also reduced. This concluded that H2SO4 treatment has led to significant removal of octahedral Al3+, Fe3+ cations and other impurities. In conclusion, this study showed the physico-chemical properties and morphology of Sayong clay were improved once treated with H2SO4 and therefore suggests better supporting material for enzyme immobilization.

scholarly journals High temperature structural study of decagonal Al-Cu-Rh quasicrystal.

2014 ◽  
Vol 70 (a1) ◽  
pp. C94-C94
Author(s):  
Pawel Kuczera ◽  
Walter Steurer
Keyword(s):  
Structural Changes ◽  
Configurational Entropy ◽  
Lattice Vibrations ◽  
X Ray Diffraction ◽  
Stabilization Mechanism ◽  
X Ray ◽  
Comparative Structure ◽  
The Stability

The structure of d(ecagonal)-Al-Cu-Rh has been studied as a function of temperature by in-situ single-crystal X-ray diffraction in order to contribute to the discussion on energy or entropy stabilization of quasicrystals (QC) [1]. The experiments were performed at 293 K, 1223 K, 1153 K, 1083 K, and 1013 K. A common subset of 1460 unique reflections was used for the comparative structure refinements at each temperature. The results obtained for the HT structure refinements of d-Al-Cu-Rh QC seem to contradict a pure phasonic-entropy-based stabilization mechanism [2] for this QC. The trends observed for the ln func(I(T1 )/I(T2 )) vs.|k⊥ |^2 plots indicate that the best on-average quasiperiodic order exists between 1083 K and 1153 K, however, what that actually means is unclear. It could indicate towards a small phasonic contribution to entropy, but such contribution is not seen in the structure refinements. A rough estimation of the hypothetic phason instability temperature shows that it would be kinetically inaccessible and thus the phase transition to a 12 Å low T structure (at ~800 K) is most likely not phason-driven. Except for the obvious increase in the amplitude of the thermal motion, no other significant structural changes, in particular no sources of additional phason-related configurational entropy, were found. All structures are refined to very similar R-values, which proves that the quality of the refinement at each temperature is the same. This suggests, that concerning the stability factors, some QCs could be similar to other HT complex intermetallic phases. The experimental results clearly show that at least the ~4 Å structure of d-Al-Cu-Rh is a HT phase therefore entropy plays an important role in its stabilisation mechanism lowering the free energy. However, the main source of this entropy is probably not related to phason flips, but rather to lattice vibrations, occupational disorder unrelated to phason flips like split positions along the periodic axis.

Hydrothermal Synthesis and Characterization of BiFeO3 Polyhedral Crystallites

2012 ◽  
Vol 174-177 ◽  
pp. 508-511
Author(s):  
Lin Lin Yang ◽  
Yong Gang Wang ◽  
Yu Jiang Wang ◽  
Xiao Feng Wang
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Synthesis And Characterization ◽  
X Ray Diffraction ◽  
Xrd Pattern ◽  
X Ray ◽  
Transmission Electron ◽  
Scanning Electron

BiFeO3 polyhedrons had been successfully synthesized via a hydrothermal method. The as-prepared products were characterized by power X-ray diffraction (XRD) pattern, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The possible mechanisms for the formation of BiFeO3 polyhedrons were discussed. Though comparison experiments, it was found that the kind of precursor played a key role on the morphology control of BiFeO3 crystals.

Investigations of Actinide Metals and Compounds under Pressure Provide Important Insights into Bonding and Chemistry

2003 ◽  
Vol 802 ◽  
Author(s):  
R. G. Haire ◽  
S. Heathman ◽  
T. Le Bihan ◽  
A. Lindbaum ◽  
M. Iridi
Keyword(s):  
Structural Changes ◽  
Chemical Properties ◽  
X Ray Diffraction ◽  
Interatomic Distances ◽  
X Ray ◽  
Effect Of Pressure ◽  
Electronic Configurations ◽  
5F Electrons ◽  
Actinide Series ◽  
Alloys And Compounds

ABSTRACTOne effect of pressure on elements and compounds is to decease their interatomic distances, which can bring about dramatic perturbations in their electronic nature and bonding, which can be reflected in changes in physical and/or chemical properties. One important issue in the actinide series of elements is the effect of pressure on the 5f-electrons. We have probed changes in electronic behavior with pressure by monitoring structure by X-ray diffraction, and have studied several actinide metals and compounds from thorium through einsteinium. These studies have employed angle dispersive diffraction using synchrotron radiation, and energy dispersive techniques via conventional X-ray sources. The 5f-electrons of actinide metals and their alloys are often affected significantly by pressure, while with compounds, the structural changes are often not linked to the involvement of 5 f-electron. We shall present some of our more recent findings from studies of selected actinide metals, alloys and compounds under pressure. A discussion of the results in terms of the changes in electronic configurations and bonding with regard to the element's position in the series is also addressed.

Sign in / Sign up

Export Citation Format

Share Document