Modeling of sheet-concentration and temperature-dependent resistivity of a suspended monolayer graphene

Polyaniline (PANI) is recognized as one of the most important conducting polymers due to its high conductivity and good stability. In this paper, polyaniline/silver (PANI/Ag) nanocomposites were synthesized by in-situ polymerization of aniline using ammonium peroxydisulphate (APS) as oxidizing agent with varying concentration of Ag nanoparticles colloids (0 ml, 25 ml and 50 ml). Silver nanoparticles were synthesized separately in colloidal form from silver nitrate (Ag2NO3) with the help of reducing agent sodium borohydride (NaBH4). The PANI/ Ag nanocomposites were characterized by XRD, SEM, AFM, UV-visible, temperature dependent resistivity and dielectric measurements. All samples show a single phase nature of the nanoparticles. The electrical resistivity as function of temperature was measured in the temperature range 298–383 K, which indicates a semiconducting to metallic transition at 373 K and 368 K for 25 ml and 50 ml silver colloid samples, respectively.

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Scattering of electrons from fractons and magnons in dilute two-dimensional antiferromagnets: Temperature-dependent resistivity in high-Tccuprates

Physical Review B ◽

10.1103/physrevb.46.14095 ◽

1992 ◽

Vol 46 (21) ◽

pp. 14095-14100 ◽

Cited By ~ 4

Author(s):

Jian-Xin Li ◽

Qing Jiang ◽

Zhe-Hua Zhang ◽

De-Cheng Tian

Keyword(s):

Two Dimensional ◽

Temperature Dependent ◽

Temperature Dependent Resistivity

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Simulation of the thermomechanical behavior of graphene/PMMA nanocomposites via continuum mechanics

International Journal of Structural Integrity ◽

10.1108/ijsi-10-2018-0078 ◽

2019 ◽

Vol 11 (5) ◽

pp. 655-669

Author(s):

Androniki Tsiamaki ◽

Nicolaos Anifantis

Keyword(s):

Mechanical Properties ◽

Accurate Method ◽

Thermomechanical Properties ◽

Van Der Waals Interactions ◽

Monolayer Graphene ◽

Graphene Sheets ◽

Temperature Dependent ◽

Content Type ◽

Graphene Layers ◽

Derived Properties

Purpose The purpose of this paper is to simulate and investigate the thermomechanical properties of graphene-reinforced nanocomposites. Design/methodology/approach The analysis proposed consists of two stages. In the first stage, the temperature-dependent mechanical properties of graphene are estimated while in the second stage, using the previously derived properties, the temperature-dependent properties of graphene-reinforced PMMA nanocomposites are investigated. In the first stage of the analysis, graphene is modeled discretely using molecular mechanics theory where the interatomic interactions are simulated by spring elements of temperature-dependent stiffness. The graphene sheets are composed of either one or more (up to five) monolayer graphene sheets connected via van der Waals interactions. However, in the second analysis stage, graphene is modeled equivalently as continuum medium and is positioned between two layers of PMMA. Also, the interphase between two materials is modeled as a medium with mechanical properties defined and bounded by the two materials. Findings The mechanical properties including Young’s modulus, shear modulus and Poisson’s ratio due to temperature changes are estimated. The numerical results show that the temperature rise and the multiplicity of graphene layers considered lead to a decrease of the mechanical properties. Originality/value The present analysis proposes an easy and accurate method for the estimation of the temperature-dependent mechanical properties of graphene-reinforced nanocomposites.

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Interpretation of metallic and semiconducting temperature-dependent resistivity of La1−xNaxMnO3 (x=0.07, 0.13) manganites

Computational Materials Science ◽

10.1016/j.commatsci.2009.11.012 ◽

2010 ◽

Vol 47 (3) ◽

pp. 839-847 ◽

Cited By ~ 26

Author(s):

Dinesh Varshney ◽

D. Choudhary ◽

M.W. Shaikh

Keyword(s):

Temperature Dependent ◽

Temperature Dependent Resistivity

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Electrical Resistivity and Magnetoresistance of the δ-FeZn10 Complex Intermetallic Phase

MRS Proceedings ◽

10.1557/opl.2013.110 ◽

2013 ◽

Vol 1517 ◽

Author(s):

P. Koželj ◽

S. Jazbec ◽

J. Dolinšek

Keyword(s):

Electrical Resistivity ◽

Intermetallic Phase ◽

Structural Complexity ◽

Weak Localization ◽

Intrinsic Disorder ◽

Atomic Clusters ◽

Charge Carriers ◽

Temperature Dependent ◽

Temperature Dependent Resistivity ◽

Complex Metallic Alloys

ABSTRACTThe δ-FeZn10 phase possesses high structural complexity typical of complex metallic alloys: a giant unit cell comprising 556 atoms, polyhedral atomic order with icosahedrally-coordinated environments, fractionally occupied lattice sites and statistically disordered atomic clusters that introduce intrinsic disorder into the structure. The electrical resistivity is large and exhibits a maximum at about 220 K. The magnetoresistance is sizeable, amounting to 1.5 % at 2 K in 9 T field. The temperature–dependent resistivity is discussed within the frame of the theory of slow charge carriers, applicable to metallic systems with weak dispersion of the electronic bands, where the electron motion changes from ballistic to diffusive upon heating. A comparison to the theory of weak localization is also made.

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