Characterization of charge transport and electrical properties in disordered organic semiconductors

The charge transfer process between substrate molecular and dopant always appears in doped organic semiconductors, so that molecular doping is a common method to improve the electrical properties by combining appropriate complexes of electron acceptor and donor molecules.

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Design and Synthesis of Two-Dimensional Covalent Organic Frameworks with Four-Arm Cores: Prediction of Remarkable Ambipolar Charge-Transport Properties

10.26434/chemrxiv.7766786.v2 ◽

2019 ◽

Author(s):

Simil Thomas ◽

Hong Li ◽

Raghunath R. Dasari ◽

Austin Evans ◽

William Dichtel ◽

...

Keyword(s):

Charge Transport ◽

Organic Semiconductors ◽

Density Functional ◽

Polymer Networks ◽

Two Dimensional ◽

Covalent Organic Frameworks ◽

X Ray Diffraction ◽

Zinc Porphyrin ◽

Design And Synthesis ◽

Predicted Values

We have considered three two-dimensional (2D) π-conjugated polymer networks (i.e., covalent organic frameworks, COFs) materials based on pyrene, porphyrin, and zinc-porphyrin cores connected via diacetylenic linkers. Their electronic structures, investigated at the density functional theory global-hybrid level, are indicative of valence and conduction bands that have large widths, ranging between 1 and 2 eV. Using a molecular approach to derive the electronic couplings between adjacent core units and the electron-vibration couplings, the three π-conjugated 2D COFs are predicted to have ambipolar charge-transport characteristics with electron and hole mobilities in the range of 65-95 cm2V-1s-1. Such predicted values rank these 2D COFs among the highest-mobility organic semiconductors. In addition, we have synthesized the zinc-porphyrin based 2D COF and carried out structural characterization via powder X-ray diffraction and surface area analysis, which demonstrates the feasability of these electroactive networks.

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Effect of the structure of cellulose acetate membranes on their permeability, electrical conductivity and rejection

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19902933 ◽

1990 ◽

Vol 55 (12) ◽

pp. 2933-2939 ◽

Cited By ~ 1

Author(s):

Hans-Hartmut Schwarz ◽

Vlastimil Kůdela ◽

Klaus Richau

Keyword(s):

Electrical Conductivity ◽

Electrical Properties ◽

Cellulose Acetate ◽

Reverse Osmosis ◽

Water Flux ◽

Cellulose Acetate Membrane ◽

Structure Parameters ◽

Dc Electrical Conductivity ◽

Cellulose Acetate Membranes

Ultrafiltration cellulose acetate membrane can be transformed by annealing into reverse osmosis membranes (RO type). Annealing brings about changes in structural properties of the membranes, accompanied by changes in their permeability behaviour and electrical properties. Correlations between structure parameters and electrochemical properties are shown for the temperature range 20-90 °C. Relations have been derived which explain the role played by the dc electrical conductivity in the characterization of rejection ability of the membranes in the reverse osmosis, i.e. rRO = (1 + exp (A-B))-1, where exp A and exp B are statistically significant correlation functions of electrical conductivity and salt permeation, or of electrical conductivity and water flux through the membrane, respectively.

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Rational design and crystal structure prediction of ring-fused double-PDI compounds as n-channel organic semiconductors: a DFT study

Physical Chemistry Chemical Physics ◽

10.1039/d1cp00008j ◽

2021 ◽

Author(s):

Suryakanti Debata ◽

Smruti R. Sahoo ◽

Rudranarayan Khatua ◽

Sridhar Sahu

Keyword(s):

Crystal Structure ◽

Charge Transport ◽

Organic Semiconductors ◽

Structure Prediction ◽

Rational Design ◽

Molecular Design ◽

Design Strategy ◽

Dft Study ◽

Crystal Structure Prediction ◽

Model Compounds

In this study, we present an effective molecular design strategy to develop the n-type charge transport characteristics in organic semiconductors, using ring-fused double perylene diimides (DPDIs) as the model compounds.

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