Query: AFM macroparticle composite electrical conductivity measurement Siemens/m

Candidate papers:

abstract: Abstract CdZnTe crystal has proved to be an excellent material to detect X ray and gamma ray. Ohmic electrode on CdZnTe wafer is one of the key factors during the fabrication of CdZnTe detector. In this work, the effect of Au/Cd composite electrode on the (111)B (Te rich surface) of CdZnTe wafers with p type conductivity (p CdZnTe) was investigated. The Au/Cd electrode was deposited on the (111)B of CdZnTe wafers by vacuum evaporation method. For comparison, the Au/Zn and Au electrodes were also deposited on CdZnTe (111)B surfaces. The surface and structural properties of the composite electrodes on the (111)B surface of CdZnTe were characterized by the AFM, XPS and SEM. The electrical properties of the electrodes were evaluated by Current Voltage (I V) test. The results show that the surfaces of the Au/Cd and Au/Zn electrodes on (111)B surface were more smooth with less foreign impurities among the interface of the electrode and CdZnTe, as compared to the Au electrode on (111)B surface. The Au/Cd composite electrode can obtain a more ideal ohmic contact than Au/Zn composite electrode on the (111)B surface of CdZnTe wafer. The Au/Cd composite electrode on (111)B surface has the lowest Schottky barrier height, which is attributed to the reduction of the influence of Te enriched surface on the metal semiconductor contact.
author_names: Liwen Ling

Jijun Zhang

Shuhao Zhao

Delong Zhang

Jiaxuan Zhang

Haozhi Shi

Ke Tang

Xiaoyan Liang

Jian Jang Huang

Jia-hua Min

Linjun Wang
title: Surface analysis and electrical measurement of the ohmic contact on p CdZnTe (111)B face with Au/Cd composite electrode
venue: Materials Science in Semiconductor Processing
year: 2019

abstract: Abstract A series of organic inorganic conducting nano composite cation exchanger have been synthesized via sol gel method and characterized by using FTIR, XRD, TGA DTA, SEM, TEM, AFM and Raman studies. The structural studies confirm the semi crystalline nature of the material with the particle size ranging from 2 to 20 nm. The observed band gap for the different samples was found to be in the range of 3.19 3.65 eV which shows that nano composite materials cover semiconducting range. Activation energy was also calculated using thermo gravimetric analysis. Electrical measurements show that the resistivity of samples is highly dependent on the of inorganic precipitate within the composite. Nano composite material has also been tested against the various bacterial Escherichia coli Bacillus thuringiensis and Pseudomonas aeruginosa and fungal strains Aspergillus nigrus Fusarium oxysporum and Penicillium chrysogenum and relatively higher activities were observed than the known antibiotics.
author_names: Syed Ashfaq Nabi

Mohammad Shahadat

Rani Bushra

Mohammad Oves

Faheem Ahmed
title: Synthesis and characterization of polyanilineZr(IV)sulphosalicylate composite and its applications (1) electrical conductivity, and (2) antimicrobial activity studies
year: 2011

abstract: HYPOTHESIS Graphene nanoplatelets (GNPs) can be dispersed in natural rubber matrices using surfactants. The stability and properties of these composites can be optimized by the choice of surfactants employed as stabilizers. Surfactants can be designed and synthesized to have enhanced compatibility with GNPs as compared to commercially available common surfactants. Including aromatic groups in the hydrophobic chain termini improves graphene compatibility of surfactants, which is expected to increase with the number of aromatic moieties per surfactant molecule. Hence, it is of interest to study the relationship between molecular structure, dispersion stability and electrical conductivity enhancement for single double and triple chain anionic graphene compatible surfactants. EXPERIMENTS Graphene philic surfactants, bearing two and three chains phenylated at their chain termini, were synthesized and characterized by proton nuclear magnetic resonance (1H NMR) spectroscopy. These were used to formulate and stabilize dispersion of GNPs in natural rubber latex matrices, and the properties of systems comprising the new phenyl surfactants were compared with commercially available surfactants, sodium dodecylsulfate (SDS) and sodium dodecylbenzenesulfonate (SDBS) Raman spectroscopy, field emission scanning electron microscopy (FESEM) atomic force microscopy (AFM) and high resolution transmission electron microscopy (HRTEM) were used to study structural properties of the materials. Electrical conductivity measurements and Zeta potential measurements were used to assess the relationships between surfactant architecture and nanocomposite properties. Small angle neutron scattering (SANS) was used to study self assembly structure of surfactants. FINDINGS Of these different surfactants, the tri chain aromatic surfactant TC3Ph3 (sodium 1,5 dioxo 1,5 bis(3 phenylpropoxy) 3 (3phenylpropoxy)carbonyl) pentane 2 sulfonate) was shown to be highly graphene compatible (nanocomposite electrical conductivity 2.22 x 10 5 S cm 1) demonstrating enhanced electrical conductivity over nine orders of magnitude higher than neat natural rubber latex matrix (1.51 x 10 14 S cm 1) Varying the number of aromatic moieties in the surfactants appears to cause significant differences to the final properties of the nanocomposites.
author_names: Azmi Mohamed

Tretya Ardyani

Suriani Abu Bakar

Masanobu Sagisaka

Yasushi Umetsu

J J Hamon

Bazura Abdul Rahim

Siti Rahmah Esa

H P S Abdul Khalil

Mohamad Hafiz Mamat

Stephen M King

Julian Eastoe
title: Rational design of aromatic surfactants for graphene/natural rubber latex nanocomposites with enhanced electrical conductivity.
venue: Journal of colloid and interface science
year: 2018

abstract: In this work, layered hybrid composites formed by tin oxide (SnO) nanoparticles synthesized by hydrolysis and poly(3,4 ethylenedioxythiophene) poly(styrenesulfonate) (PEDOT:PSS) have been analyzed. Prior to the composite study, both SnO and PEDOT:PSS counterparts were characterized by diverse techniques, such as X ray diffraction (XRD) Raman spectroscopy, transmission electron microscopy (TEM) photoluminescence (PL) atomic force microscopy (AFM) optical absorption and Hall effect measurements. Special attention was given to the study of the stability of the polymer under laser illumination, as well as the analysis of the SnO to SnO2 oxidation assisted by laser irradiation, for which different laser sources and neutral filters were employed. Synergetic effects were observed in the hybrid composite, as the addition of SnO nanoparticles improves the stability and electrical conductivity of the polymer, while the polymeric matrix in which the nanoparticles are embedded hinders formation of SnO2. Finally, the Si passivation behavior of the hybrid composites was studied.
author_names: Antonio Vazquez-Lopez

Anisa Yaseen

David Maestre

Julio Ramirez-Castellanos

Erik Stensrud Marstein

Smagul Zh Karazhanov

A Cremades
title: Synergetic Improvement of Stability and Conductivity of Hybrid Composites formed by PEDOT:PSS and SnO Nanoparticles
venue: Molecules
year: 2020

abstract: Abstract An ion imprinting polymer (IIP) electrochemical sensors based on chitosan graphene oxide composites polymer modified glassy carbon electrode (CS/GO IIP) was developed for the highly sensitive and selective detection of Cu (II) by the dip coating method. The Cu (II) ion imprinted polymers were synthesized by chemically cross linking with epichlorohydrin after the CS/GO/Cu (II) composite dropped on the glassy carbon electrode surface. The introduction of GO can improve the electrical conductivity of the electrode and amplify the electrochemical signal. The sensor was characterized by FT IR, EDS, SEM, AFM, Raman spectroscopy and electrochemical measurements. Under the optimized conditions, a linear dependence was observed from 0.5 to 100 mmol/L with a detection limit of 0.15 mmol/L. The detection of Cu (II) was hardly interfered by the traditional metal cations. The CS/GO IIP sensor showed excellent reproducibility via repetitive differential pulse anodic stripping voltammetry and the RSD was 3.3% More importantly, the performance of CS/GO IIP sensor was verified in tap and river water samples and has an acceptable recovery rates.
author_names: Pengju Wei

Zhigang Zhu

Runmin Song

Zhan-Hong Li

Cheng Chen
title: An ion imprinted sensor based on chitosan graphene oxide composite polymer modified glassy carbon electrode for environmental sensing application
venue: Electrochimica Acta
year: 2019

abstract: Abstract A new composite material from epoxidized natural rubber (ENR 50) and polyaniline have been successfully prepared. Aniline which was polymerized in the presence of dodecylbenzene sulfonic acid (DBSA) then added to ENR 50 for the preparations of ENR 50/Pani.DBSA composite films. The hydrogen bonding which contribute to the formation of ENR 50/Pani.DBSA composites was observed in FT IR, UV Visible and DSC. It showed hydrogen bonding interactions between the epoxy groups in ENR 50 and the amine groups in Pani.DBSA. The morphologies of the prepared materials were investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM) SEM and conductivity measurements revealed that the percolation threshold is at 2.5 w% of Pani.DBSA content. Atomic force microscopy (AFM) micrographs showed that ENR 50 with 5 wt% Pani.DBSA addition has the lowest surface roughness. In addition thermogravimetric analysis indicates improved thermal stability at low Pani.DBSA content. DSC measurements revealed that Tg value increases with increasing Pani.DBSA, indicating that the formation of homogenous composite material. Nanoindentation results show that the hardness (H) and Young's modulus (Es) increased with higher addition of Pani.DBSA polymer.
author_names: Wan Ahmad Kamil Mahmood

Mohammad Hossein Azarian
title: Thermal, surface, nanomechanical and electrical properties of epoxidized natural rubber (ENR 50) polyaniline composite films
year: 2015

abstract: Jute fibers (JFs) coated with multiwall carbon nanotubes (MWCNTs) have been introduced in a natural rubber (NR) matrix creating a three dimensional (3D) electrically conductive percolated network. The JF CNT endowed electrical conductivity and thermoelectric properties to the final composites. CNT networks fully covered the fiber surfaces as shown by the corresponding scanning electron microscopy (SEM) analysis. NR/JF CNT composites, at 10, 20 and 30 phr (parts per hundred gram of rubber) have been manufactured using a two roll mixing process. The highest value of electrical conductivity (s) was 81 S/m for the 30 phr composite. Thermoelectric measurements revealed slight differences in the Seebeck coefficient (S) while the highest power factor (PF) was 1.80 x 10 2 mW/m K 2 for the 30 phr loading. The micromechanical properties and electrical response of the composite's conductive interface have been studied in peak force tapping quantitative nanomechanical (PFT QNM) and conductive atomic force microscopy (c AFM) mode. The JF CNT create an electrically percolated network at all fiber loadings endowing electrical and thermoelectric properties to the NR matrix, considered thus as promising thermoelectric stretchable materials.
author_names: Lazaros Tzounis

Markos Petousis

Marco Liebscher

Sotirios A Grammatikos

Nectarios Vidakis
title: Three Dimensional (3D) Conductive Network of CNT Modified Short Jute Fiber Reinforced Natural Rubber: Hierarchical CNT Enabled Thermoelectric and Electrically Conductive Composite Interfaces
venue: Materials
year: 2020

abstract: Conductive particle filled polymer composites are promising materials for applications where both the merits of polymer and conductivity are required. The electrical properties of such composites are controlled by the particle percolation network present in the polymeric matrix. In this study, the electrical properties of crosslinked carbon black epoxy amine (CB EA) composites with various CB concentrations are studied at room temperature as a function of the AC frequency f A transition at critical frequency f c from the DC plateau s DC to a frequency dependent part was observed. Conductivity mechanisms for f f c and f f c were investigated. By considering the fractal nature, conduction for f f c was verified to be intra cluster charge diffusion. For f f c with the assistance of conductive atomic force microscopy (C AFM) the conduction behavior of individual clusters can be observed, revealing both linear and nonlinear I V characteristics. By combining microtoming and C AFM measurements, 3D reconstructed images offer direct evidence that the percolating network of these materials consists of both a low conductivity part, in which the charge transports through tunneling, and a high conductivity part, which shows ohmic electrical properties. Nevertheless, for these CB EA composites, the presence of these non ohmic contacts still leads to Arrhenius type behavior for the macroscopic conductivity.
author_names: A N Alekseev

T H Wu

Leo G J van der Ven

Rolf A T M van Benthem

Gijsbertus With
title: Global and local conductivity in percolating crosslinked carbon black/epoxy amine composites
venue: Journal of Materials Science
year: 2020

abstract: The role of the interfaces on the optoelectronical properties of porphyrin fullerene composites has been studied by means of ultraviolet visible (UV Vis) and Raman spectroscopy, atomic force microscopy (AFM) and electric conductivity measurements. A simple method of synthesis of donor acceptor complexes has been performed by subsequent deposition of C60 fullerene and tetraphenylporphyrin (H2TPP) thin films, using physical vapor deposition (PVD) on a (100) silicon substrate. UV Vis spectra showed that the interaction of p orbitals leads to a more ordering for the dipole moments arrangement and the p orbitals overlapping between C60 and H2TPP molecules. Besides, Raman spectra presented intensity changes at 960 and 1000 cm 1, both related to the vibration of the pyrrole ring and the rocking of the H on the C atoms within the macrocycle. Therefore, it can be expected that the interface C60 H2TPP should have a main role in the electric response of the multilayer films. The measurements of surface conductivity indicated that interface has specific contribution, and the value of surface conductivity is enhanced by charge delocalization mechanisms occur by p p stacking interactions. It was found that the transversal conductivity of 3 layer films was enhanced by a factor of 4 in comparison to 2 layer film, due to charge transfer mechanisms occur in the junctions that could extend the diffusion length of the charge carriers. Finally, the interface generated between C60 and H2TPP films, without any linking molecule, enhance charge transport mechanism through the films.
author_names: Edgar Alvarez-Zauco

Hugo M Sobral

Erick Martinez-Loran
title: Morphological, Optical and Electrical Characterization of the Interfaces in Fullerene Porphyrin Thin Films.
venue: Journal of nanoscience and nanotechnology
year: 2020

abstract: Abstract In this research article, ultrasound assisted exfoliation in a liquid phase production process has been adopted for synthesis of 2D Molybdenum Disulfide (MoS2) The energetic governing dispersion of Nano sheets in a wide range of solvents has been studied. Nano sheets dispersion in an aqueous media has been prepared with the help of high surface tension solvents like N Methyl 1, 2 Pyyrolidone (NMP) and Tetrahydrofuran (THF) The dispersion was composed of layers of MoS2 with some quantities of mono and bi layer materials were observed. Scanning Electron Microscopy (SEM) X Rays Diffractometry (XRD) Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM) were used to characterize the samples; SEM clearly evident the microstructure of samples while XRD shows the peaks of filler in the polystyrene composite membrane. AFM confirmed the presence of 2D MoS2 with 0.9 7 nm thickness range of MoS2 flake. In order to get the surfactant stabilized dispersed material, the processing was enhanced using prolonged sonication to yield maximized concentration. Liquid phase exfoliation allows dispersion to be cast into thin film by using vacuum filtration assembly. The obtained film is dispersed in solvent and is used in polymers. Two sets of concentrations (0.01, 0.03, 0.05 and 0.07% by wt. and 0.1, 0.3, 0.7 and 0.9% by wt. were analyzed and it was observed during tensile testing that modulus of elasticity (E) percentage elongation and ultimate tensile strength (UTS) of composite material increases maximum up to 741times, 374 times and 200 times as compared to base polymer (PS) respectively. Furthermore, dielectric constant, dielectric loss and electrical conductivity of PS MoS2 were also evaluated and finding clearly pointed out that filler loading of MoS2 has considerable effects on these properties and maximum value of dielectric constant is 3.6 at 0.9% loading as compared with of pure PS (polystyrene) matrix. On the other hand, variation in dielectric loss from lower to higher frequency is 2.5 x 10 2 on average which is not so significant. Electrical conductivity was also accounted, and measurement results are indicating that conductivity was almost constant at lower frequency in range of 10 10 due to low field strength, but it increases to 10 9 value at higher frequency due to hoping mechanism and network formation of filler.
author_names: Muhammad Arshad

Hassan Raza

Muhammad Bilal Khan

Arif Hussain
title: Synthesis of 2D Molybdenum Disulfide (MoS2) for enhancement of mechanical and electrical properties of polystyrene (PS) polymer
year: 2020