scholarly journals Fabrication and Characterization of Composite Containing HCl-Doped Polyaniline and Fe Nanoparticles

2012 ◽  
Vol 2012 ◽  
pp. 1-7 ◽  
Author(s):  
Rongcheng Liu ◽  
Hong Qiu ◽  
Hua Zong ◽  
Chunying Fang
Keyword(s):  
Carrier Transport ◽  
Room Temperature ◽  
Heating Temperature ◽  
Room Temperature Ferromagnetism ◽  
Three Dimensional ◽  
Composite Pellet ◽  
Fe Nanoparticles ◽  
Doped Polyaniline ◽  
Dimensional Variable

HCl-doped polyaniline powder (HCl-PANI) was synthesized by using a polymerization procedure. Fe nanoparticles were then deposited on the HCl-PANI at room temperature by direct current magnetron sputtering. After this process the HCl-PANI-Fe composite was obtained. Fe nanoparticle size in the composite is about 100 nm. HCl-PANI structure is not influenced by the Fe nanoparticles. The composite pellet has room temperature ferromagnetism and a conductivity of 0.25 S/cm. Temperature dependence of the conductivity reveals that a carrier transport mechanism in the composite is three-dimensional variable range hopping. Thermogravimetric analysis reveals that a weight loss of the HCl-PANI-Fe composite is smaller than that of the HCl-PANI for the same heating temperature when the temperature exceeds 230°C.

scholarly journals Electrical Double Percolation of Polybutadiene/Polyethylene Glycol Blends Loaded with Conducting Polymer Nanofibers

Polymers ◽  
2020 ◽  
Vol 12 (11) ◽  
pp. 2658
Author(s):  
Jun Morita ◽  
Takanori Goto ◽  
Shinji Kanehashi ◽  
Takeshi Shimomura
Keyword(s):  
Polyethylene Glycol ◽  
Critical Exponent ◽  
Percolation Threshold ◽  
Field Effect ◽  
Carrier Transport ◽  
Three Dimensional ◽  
Scanning Force Microscopy ◽  
Three Dimensions ◽  
Dimensional Variable ◽  
Double Percolation

The critical phenomena of double percolation on polybutadiene (PB)/polyethylene glycol (PEG) blends loaded with poly-3-hexylthiophene (P3HT) nanofibers is investigated. P3HT nanofibers are selectively localized in the PB phase of the PB/PEG blend, as observed by scanning force microscopy (SFM). Moreover, double percolation is observed, i.e., the percolation of the PB phase in PB/PEG blends and that of the P3HT nanofibers in the PB phase. The percolation threshold (φcI) and critical exponent (tI) of the percolation of the PB phase in PB/PEG blends are estimated to be 0.57 and 1.3, respectively, indicating that the percolation exhibits two-dimensional properties. For the percolation of P3HT nanofibers in the PB phase, the percolation threshold (φcII) and critical exponent (tII) are estimated to be 0.02 and 1.7, respectively. In this case, the percolation exhibits properties in between two and three dimensions. In addition, we investigated the dimensionality with respect to the carrier transport in the P3HT nanofiber network. From the temperature dependence of the field-effect mobility estimated by field-effect transistor (FET) measurements, the carrier transport was explained by a three-dimensional variable range hopping (VRH) model.

Characterization of HCl-Doped Polyaniline-Ag Nanocomposite Prepared by Chemical and Physical Combinative Method

2013 ◽  
Vol 677 ◽  
pp. 55-60 ◽  
Author(s):  
Bing Hu ◽  
Yang Cao ◽  
Rong Ying Huang ◽  
Jian Bo Fu ◽  
Hong Qiu
Keyword(s):  
Grain Size ◽  
Ag Nanoparticles ◽  
Room Temperature ◽  
Rf Sputtering ◽  
Chemical Polymerization ◽  
Average Grain Size ◽  
Doped Polyaniline ◽  
Agcl Nanoparticles

HCl-doped polyaniline (HCl-PANI) powder is synthesized by using a chemical polymerization procedure. Then Ag nanoparticles are deposited on the HCl-PANI at room temperature by RF sputtering. After this process, the nanocomposite is obtained by the chemical and physical combinative method. The nominal Ag content in the nanocomposite ranges from 1.0 wt% to 3.3 wt%. For all the nanocomposites, the Ag nanoparticles convert to AgCl nanoparticles. Namely, the HCl-PANI-AgCl nanocomposites are obtained. A content of the AgCl in the nanocomposite increases with increasing Ag content. The AgCl nanoparticle consists of many grains. An average grain size of AgCl is about 40 nm and is independent of the Ag content. A conductivity of the nanocomposite decreases with increasing Ag content.

Room-Temperature Ferromagnetism in Doped Face-Centered Cubic Fe Nanoparticles

Small ◽  
2006 ◽  
Vol 2 (6) ◽  
pp. 804-809 ◽  
Author(s):  
Bingqing Wei ◽  
Mutsuhiro Shima ◽  
Ranjit Pati ◽  
Saroj K. Nayak ◽  
David J. Singh ◽  
...  
Keyword(s):  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Face Centered Cubic ◽  
Fe Nanoparticles ◽  
Face Centered

THE GROWTH AND CHARACTERIZATION OF ROOM TEMPERATURE FERROMAGNETIC WIDEBAND-GAP MATERIALS FOR SPINTRONIC APPLICATIONS

2006 ◽  
Vol 16 (02) ◽  
pp. 515-543
Author(s):  
MATTHEW H. KANE ◽  
MARTIN STRASSBURG ◽  
WILLIAM E. FENWICK ◽  
ALI ASGHAR ◽  
IAN T. FERGUSON
Keyword(s):  
Room Temperature ◽  
Magnetic Semiconductors ◽  
Room Temperature Ferromagnetism ◽  
Dilute Magnetic Semiconductors ◽  
Chemical Vapor ◽  
Wide Bandgap ◽  
Organic Chemical ◽  
Ferromagnetic Behavior ◽  
Spintronic Devices

Wide-bandgap dilute magnetic semiconductors (DMS), such as transition-metal doped ZnO and GaN , have gained attention for use in spintronic devices because of predictions and experimental reports of room temperature ferromagnetism which may enable their use in spintronic devices. However, there has been some debate over the source of ferromagnetism in these materials. This paper focuses on the high quality growth of wide bandgap DMS, and the characterization of Zn 1-x Mn x O produced by melt-growth techniques and Ga 1-x Mn x N grown by metal organic chemical vapor deposition (MOCVD). High resolution X-ray diffraction results revealed no second phases in either the ZnO crystals or the GaN films. Undoped as-grown, bulk crystals of Zn 1-x Mn x O and Zn 1-x Co x O crystals are shown to be paramagnetic at all temperatures. In contrast, the Ga 1-x Mn x N films showed ferromagnetic behavior at room temperature under optimum growth conditions. Experimental identification of the Mn ion charge state and the presence of bands in the bandgap of GaN are investigated by optical spectroscopy and electron spin paramagnetic resonance (EPR). It is shown that the broadening of states in the Mn 3d shell scaled with Mn concentration, and that optical transitions due to this band correlated with the strong ferromagnetism in these samples. However, this band disappeared with an increase in free electron concentration provided by either annealing or doping. Raman studies of Ga 1-x Mn x N revealed two predominant Mn -related modes featured with increasing concentration, a broad disorder related structure at 300cm-1 and a sharper peak at 669cm-1 This works show that the development of practical ferromagnetic wide bandgap DMS materials for spintronic applications will require both the lattice site introduction of Mn as well as careful control of the background defect concentration to optimize these materials.

scholarly journals Tuning the Room Temperature Ferromagnetism in Fe5GeTe2 by Arsenic Substitution

2D Materials ◽  
2021 ◽  
Author(s):  
Andrew May ◽  
Jiaqiang Yan ◽  
Raphael Hermann ◽  
Mao-Hua Du ◽  
Michael A McGuire
Keyword(s):  
Magnetic Properties ◽  
Curie Temperature ◽  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Fine Tuning ◽  
The Individual ◽  
Curie Temperature Tc ◽  
Antiferromagnetic Behavior ◽  
Magnetic Sublattices

Abstract In order to tune the magnetic properties of the cleavable high-Curie temperature ferromagnet Fe5-xGeTe2, the effect of increasing the electron count through arsenic substitution has been investigated. Small additions of arsenic (2.5 and 5%) seemingly enhance ferromagnetic order in polycrystalline samples by quenching fluctuations on one of the three magnetic sublattices, whereas larger As concentrations decrease the ferromagnetic Curie temperature (TC) and saturation magnetization. This work also describes the growth and characterization of Fe4.8AsTe2 single crystals that are structurally analogous to Fe5-xGeTe2 but with some phase stability complications. Magnetization measurements reveal dominant antiferromagnetic behavior in Fe4.8AsTe2 with a Neel temperature of TN ≈42K. A field-induced spin-flop below TN results in a switch from negative to positive magnetoresistance, with significant hysteresis causing butterfly-shaped resistance loops. In addition to reporting the properties of Fe4.8GeTe2, this work shows the importance of manipulating the individual magnetic sublattices in Fe5-xGeTe2 and motivates further efforts to control the magnetic properties in related materials by fine tuning of the Fermi energy or crystal chemistry.

scholarly journals Synthesis of iron sand into nano Mn-Ferrite

2014 ◽  
Vol 9 (4) ◽  
Author(s):  
Agus Yulianto ◽  
Sulhadi Sulhadi ◽  
Ahmad Lutfi Isnaeni Azis ◽  
Eli Dayati
Keyword(s):  
Room Temperature ◽  
Heating Temperature ◽  
Sol Gel ◽  
Precipitation Process ◽  
Average Particle ◽  
Mixed Solution ◽  
Nanosized Powder ◽  
Heating Treatment ◽  
Impurity Elements

Magnetic material, Mn-Ferrite, was prepared from iron sand using precipitation and sol-gel methods. The methods were applied to produce a homogenous and nanosized powder. The precipitation process was taken place at room temperature. MnO2 and Fe3O4 were dissolved with HCl solution to obtained MnCl2, FeCl2 and FeCl3 and the resulted solution were mixed. NH4OH and NaOH solutions were added into mixed solution to produce precipitated material. At the heating temperature of 70°C, 59% of (Mn,Fe)2O3 was obtained with its particle size around 1-10 nm. By applying sol-gel method, the iron sand was processed into iron (III) nitrate using nitric acid. Then Iron (III) nitrate was mixed with manganese (II) nitrate in the EG solvent and heated for 2 hours in 100°C until gel was formed. To get the powder, the gel was dried at 150°C for 2 hours and then continued into 350 -700°C for 2 hours. The XRD characterization shows that the powder produced from 350°C heating contain 100% of (Mn,Fe)3O4 with spinel cubic structure. At the heating treatment of 700°C, the compound was changed into (Mn,Fe)2O3 and MnFeO3. By applying Scherrer method, it was known that the average particle sizewas 1 nm and homogenous. The XRF characterization of the material resulted by both of the methods indicates that there were impurity elements such as Ti, Mo, Zn, Ca, Cu and Ni exist in the sample, since the study was used row material of iron sand.

scholarly journals Effects of Temperature on Bending Properties of Three-Dimensional and Five-Directional Braided Composite

Molecules ◽  
2019 ◽  
Vol 24 (21) ◽  
pp. 3977
Author(s):  
Li ◽  
Jia ◽  
Pei ◽  
Wan ◽  
Li ◽  
...  
Keyword(s):  
Epoxy Resin ◽  
Room Temperature ◽  
Bending Strength ◽  
Heating Temperature ◽  
Three Dimensional ◽  
Heating Time ◽  
Resin Composites ◽  
Bending Properties ◽  
Different Temperatures ◽  
Epoxy Resin Composites

The bending properties of three-dimensional (3Dim) and five-directional (5Dir) braided/epoxy resin composites at room temperature, 90 °C, 110 °C, and 150 °C and heating for 0.25 h, 10 h, and 30 h, respectively, were studied. The effect of different temperatures and heating times on the bending property of these composites was discussed. The results showed that the bending strength of these composites at 90 °C, 110 °C, and 150 °C and heating time of 0.25 h is 33.86%, 46.27%, and 83.94% lower, respectively, than that at room temperature. In addition, 3Dim–5Dir braided composites exhibit different damage modes at different temperatures, revealing different failure mechanisms. Heating temperature has greater influence on the bending properties of these composites than heating time. The results provided a basis for the application of resin-based 3Dim–5Dir braided/epoxy resin composites at different temperatures.

scholarly journals Synthesis, X-Ray Structure, and Characterization of a Complex Containing the Hexakis(urea)cobalt(II) Cation and Lattice Urea Molecules

2007 ◽  
Vol 2007 ◽  
pp. 1-7 ◽  
Author(s):  
Labrini Drakopoulou ◽  
Constantina Papatriantafyllopoulou ◽  
Aris Terzis ◽  
Spyros P. Perlepes ◽  
Evy Manessi-Zoupa ◽  
...  
Keyword(s):  
Room Temperature ◽  
Three Dimensional ◽  
Monoclinic Space Group ◽  
Two Dimensional ◽  
X Ray ◽  
Lattice Constants ◽  
Dimensional Network ◽  
Different Types ◽  
Hydrogen Bonded

The 12: 1 reaction of urea (U) with CoI2in EtOH yielded the “clathrate-coordination” compound[CoU6]I2·4U (1). The complex crystallizes in the monoclinic space group P21/c. The lattice constants area= 9.844(4),b= 7.268(3),c= 24.12(1) Å, andβ=98.12(1)∘. The crystal structure determination demonstrates the existence of octahedral[CoU6]2+cations,I-counterions, and two different types (twoU1and twoU2) of hydrogen-bonded, lattice urea molecules. The[CoU6]2+cations and theU1lattice molecules form two-dimensional hydrogen-bonded layers which are parallel to theabplane. TheI-anions are placed above and below each layer, and are hydrogen bonded both toU1molecules and[CoU6]2+cations. EachU2molecule is connected to a[CoU6]2+cation through anN–H⋯Ohydrogen bond resulting in a three-dimensional network. Room temperature magnetic susceptibility and spectroscopic (solid-state UV/Vis, IR, Raman) data of1are discussed in terms of the nature of bonding and the known structure.

Room temperature ferromagnetism and structural characterization of Fe,Ni co-doped ZnO nanocrystals

2013 ◽  
Vol 287 ◽  
pp. 287-292 ◽  
Author(s):  
Pooja Dhiman ◽  
Khalid Mujasam Batoo ◽  
R.K. Kotnala ◽  
Jagdish Chand ◽  
M. Singh
Keyword(s):  
Structural Characterization ◽  
Room Temperature ◽  
Room Temperature Ferromagnetism ◽  
Zno Nanocrystals ◽  
Doped Zno ◽  
Co Doped

scholarly journals Оптические свойства трехмерных островков InGaP(As), сформированных методом замещения элементов пятой группы

2021 ◽  
Vol 129 (2) ◽  
pp. 218
Author(s):  
Н.В. Крыжановская ◽  
А.С. Драгунова ◽  
С.Д. Комаров ◽  
А.М. Надточий ◽  
А.Г. Гладышев ◽  
...  
Keyword(s):  
Optical Properties ◽  
Carrier Transport ◽  
Room Temperature ◽  
Three Dimensional ◽  
Wavelength Shift ◽  
Nonradiative Recombination ◽  
Two Dimensional ◽  
Photoluminescence Excitation ◽  
Excitation Spectra ◽  
Recombination Centers

Photoluminescence spectroscopy (PL) has been used to study the optical properties of three-dimensional quantum-sized InGaPAs islands formed by substituting phosphorus by arsenic in an InGaP layer deposited on GaAs directly during epitaxial growth. PL line of the formed array of islands is in the range of 950–1000 nm at room temperature. Studies of PL in the temperature range 78–300 K indicate a significant inhomogeneity of the island array, the presence of nonradiative recombination centers, and carrier transport between islands. We observe in the photoluminescence excitation spectra a line associated with absorption in the residual two-dimensional InGaPAs layer. Annealing of the structures results in 300% increase of the PL intensity at room temperature with an insignificant short-wavelength shift of the island PL line, and also in improvement of the homogeneity within the island array.

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