Probing Out-Of-Plane Charge Transport in Organic Semiconductors Using Conductive Atomic Force Microscopy.

High contact resistance remains the primary obstacle that hinders further advancements of organic semiconductors (OSCs) in electronic circuits. While significant effort has been directed toward lowering the energy barrier at OSC/metal contact interfaces, approaches toward reducing another major contributor to overall contact resistance - the bulk resistance - have been limited to minimizing the thickness of OSC films. However, the out-of-plane conductivity of OSCs, a critical aspect of bulk resistance, has largely remained unaddressed.

Impact of hydrophilic side chains on the thin film transistor performance of a benzothieno-benzothiophene derivative.

Side-chain engineering in molecular semiconductors provides a versatile toolbox for precisely manipulating the material's processability, crystallographic properties, as well as electronic and optoelectronic characteristics. This study explores the impact of integrating hydrophilic side chains, specifically oligoethylene glycol (OEG) units, into the molecular structure of the small molecule semiconductor, 2,7-bis(2(2-methoxy ethoxy)ethoxy) benzo[]benzo[4,5] thieno[2,3-] thiophene (OEG-BTBT). The investigation includes a comprehensive analysis of thin film morphology and crystallographic properties, along with the optimization of deposition parameters for improving the device performance.

Effects of Processing-Induced Contamination on Organic Electronic Devices.

Organic semiconductors are a family of pi-conjugated compounds used in many applications, such as displays, bioelectronics, and thermoelectrics. However, their susceptibility to processing-induced contamination is not well understood. Here, it is shown that many organic electronic devices reported so far may have been unintentionally contaminated, thus affecting their performance, water uptake, and thin film properties.

High-Performance Humidity Sensing in π-Conjugated Molecular Assemblies through the Engineering of Electron/Proton Transport and Device Interfaces.

The development of systems capable of responding to environmental changes, such as humidity, requires the design and assembly of highly sensitive and efficiently transducing elements. Such a challenge can be mastered only by disentangling the role played by each component of the responsive system, thus ultimately achieving high performance by optimizing the synergistic contribution of all functional elements. Here, we designed and synthesized a novel [1]benzothieno[3,2-][1]benzothiophene derivative equipped with hydrophilic oligoethylene glycol lateral chains (OEG-BTBT) that can electrically transduce subtle changes in ambient humidity with high current ratios (>10) at low voltages (2 V), reaching state-of-the-art performance.

Electrochromic Sensors Based on Conducting Polymers, Metal Oxides, and Coordination Complexes.

Electrochromic sensors offer multi-mode registration of analytical signal based on combination of electrochemical and optical techniques. This emerging direction of analytical chemistry is relatively new; therefore, it has very high potential for various applications in chemical and biochemical analysis. Properties of sensors based on various electrochromic materials such as polymers, polymer derivatives, polymer composites, metal oxides, metal oxide complexes, phthalocyanines, porphyrins, and dyes are critically overviewed, evaluated, and compared.

Experimental and Theoretical Investigations of an Electrochromic Azobenzene and 3,4-Ethylenedioxythiophene-based Electrochemically Formed Polymeric Semiconductor.

An electrochromic material based on azobenzene and 3,4-ethylenedioxythiophene (EDOT) semiconducting layer was electrochemically deposited on an indium tin oxide coated glass electrode. Chemical synthesis of the azobenzene and EDOT-based chromophore (DAE) and electrochemical formation of its corresponding polymer (pDAE) are reported. The electrochromic properties of the synthesized polymer pDAE were investigated by electrochemical and spectroelectrochemical methods.