Search results for "electrical conductivity."
showing 10 items of 42 documents
Stable n-type thermoelectric multilayer thin films with high power factor from carbonaceous nanofillers
2016
Abstract High power factor n-type organic thermoelectric nanocomposites are assembled by alternately depositing double walled-nanotubes (DWNT), stabilized by polyethyleneimine (PEI), and graphene stabilized by polyvinylpyrrolidone (PVP), from water using the layer-by-layer (LbL) assembly technique. This unique combination of carbon nanomaterials exhibits an electrical conductivity of 300 S cm−1 and a relatively stable power factor of 190 μW m−1 K−2 at room temperature.
Electrical conductivity and strong luminescence in copper Iodide double chains with isonicotinato derivatives
2015
Direct reactions between CuI and isonicotinic acid (HIN) or the corresponding esters, ethyl isonicotinate (EtIN) or methyl isonicotinate (MeIN), give rise to the formation of the coordination polymers [CuI(L)] with L=EtIN (1), MeIN (2) and HIN (3). Polymers 1-3 show similar structures based on a CuI double chain in which ethyl-, methyl isonicotinate or isonicotinic acid are coordinated as terminal ligands. Albeit, their supramolecular architecture differs considerably, affecting the distances and angles of the central CuI double chains and thereby their physical properties. Hence, the photoluminescence shows remarkable differences; 1 and 2 show a strong yellow emission, whereas 3 displays a…
Morphology and Band Structure of Orthorhombic PbS Nanoplatelets: An Indirect Band Gap Material
2021
PbS quantum dots and nanoplatelets (NPLs) are of enormous interest in the development of optoelectronic devices. However, some important aspects of their nature remain unclear. Recent studies have revealed that colloidal PbS NPLs may depart from the rock-salt crystal structure of bulk and form an orthorhombic (Pnma) modification instead. To gain insight into the implications of such a change over the optoelectronic properties, we have synthesized orthorhombic PbS NPLs and determined the lattice parameters by means of selected area electron diffraction measurements. We have then calculated the associated band structure using density functional theory with Perdew–Burke–Ernzerhof functional fo…
A new route for the preparation of flexible skin–core poly(ethylene-co-acrylic acid)/polyaniline functional hybrids
2011
Abstract Surface modification of polymeric films is a way to obtain final products with high performance for many specific and ad hoc tailored applications, e.g. in functional packaging, tissue engineering or (bio)sensing. The present work reports, for the first time, on the design and development of surface modified ethylene–acrylic acid copolymer (EAA) films with polyaniline (PANI), with the aim of inducing electrical conductivity and potentially enable the electronic control of a range of physical and chemical properties of the film surface, via a new “grafting from” approach. In particular, we demonstrate that PANI was successfully polymerized and covalently grafted onto flexible EAA su…
Structural, electronic, and electrical properties of an Undoped n-Type CdO thin film with high electron concentration
2014
Transparent conducting metal oxides (TCOs) combine the properties of optical transparency in the visible region with a high electrical conductivity. They are a critical component as the window electrode in liquid crystal and electroluminescent display devices, as well as in many designs of solar cells now under development. Sn-doped In2O3 is currently the most important TCO, but it suffers from some drawbacks. These include the high cost of indium, weak optical absorption in the blue-green region, as well as chemical instability that leads to corrosion phenomena in organic light-emitting devices. Indium tin oxide (ITO) films are also brittle and of relatively low durability. A number of oth…
Electrical transport in carbon black-epoxy resin composites at different temperatures
2013
Citation: J. Appl. Phys. 114, 033707 (2013); doi: 10.1063/1.4815870 (Received 3 May 2013; accepted 27 June 2013; published online 17 July 2013) Results of broadband electric/dielectric properties of different surface area—carbon black/epoxy resin composites above the percolation threshold are reported in a wide temperature range (25–500 K). At higher temperatures (above 400 K), the electrical conductivity of composites is governed by electrical transport in polymer matrix and current carriers tunneling from carbon black clusters to polymer matrix. The activation energy of such processes decreases when the carrier concentration increases, i.e., with the increase of carbon black concentration…
On the temperature dependence of the electrical conductivity in hot quenched lattice QCD
2011
Extending our recent work, we report on a calculation of the vector current correlation function for light valence quarks in the deconfined phase of quenched QCD in the temperature range 1.16Tc<T<2.98Tc. After performing a systematic analysis of the in fluence of cut-off effects on light quark meson correlators using clover improved Wilson fermions, we discuss resulting constraints on the electrical conductivity in a quark gluon plasma.
Nanocarbon broadband analysis, temperature dependent dielectric properties and percolation thresholds
2013
The results of a broadband dielectric investigation of multi-walled CNT (MWCNT)/epoxy resin composites in wide temperature range from room temperature to 450 K are reported. Far below the percolation threshold (0.25 wt% MWCNT) the dielectric properties of the composite are mostly determined by alpha relaxation in pure polymer matrix. Close to the percolation threshold the composite shows the negative temperature coefficient (NTC) effect in the temperature region, where the pure polymer matrix becomes conductive. The activation energy increases with the MWCNT concentration far below the percolation threshold and decreases close to it (1.5 wt% MWCNT). The dielectric analysis of the MWCNT/epox…
TCO/Ag/TCO transparent electrodes for solar cells application
2014
Among transparent electrodes, transparent conductive oxides (TCO)/metal/TCO structures can achieve optical and electrical performances comparable to, or better than, single TCO layers and very thin metallic films. In this work, we report on thin multilayers based on aluminum zinc oxide (AZO), indium tin oxide (ITO) and Ag deposited by RF magnetron sputtering on soda lime glass at room temperature. The TCO/Ag/TCO structures with thicknesses of about 50/10/50 nm were deposited with all combinations of AZO and ITO as top and bottom layers. While the electrical conductivity is dominated by the Ag intralayer irrespective of the TCO nature, the optical transmissions show a dependence on the natur…
Control and Simplicity in the Nanoprocessing of Semiconducting Copper-Iodine Double Chain Coordination Polymers
2018
This document is the Accepted Manuscript version of a Published Work that appeared in final form in Inorganic Chemistry © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see https://pubs.acs.org/doi/abs/10.1021/acs.inorgchem.8b00364