Organic Semiconductors for Optically Triggered Neural Interfacing: The Impact of Device Architecture in Determining Response Magnitude and Polarity

AbstractOrganic semiconductors exhibiting complementary-type carrier mobility are the key components for the development of the field of “plastic electronics”. We present here a novel series of αω- and isomerically pure β,β'-diperfluorohexyl-substituted thiophene and study the impact of fluoroalkyl substitution and conjugation length vìs-à-vìs the corresponding fluorinefree analogues. Trends between the fluorinated and fluorine-free families in molecular packing, HOMO-LUMO gap, and π-π interactions are found to be strikingly similar. TFT measurements indicate that all members of the fluorinated series are n-type semiconductors

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N- and P-Type Building Blocks for Organic Electronics Based on Oligothiophene Cores

MRS Proceedings ◽

10.1557/proc-771-l12.8/h11.8 ◽

2003 ◽

Vol 771 ◽

Cited By ~ 2

Author(s):

Antonio Facchetti ◽

Myung-Han Yoon ◽

Howard E. Katz ◽

Melissa Mushrush ◽

Tobin J. Marks

Keyword(s):

Organic Semiconductors ◽

Organic Electronics ◽

Carrier Mobility ◽

Building Blocks ◽

Molecular Packing ◽

Conjugation Length ◽

Π Interactions ◽

P Type ◽

The Impact ◽

Homo Lumo

AbstractOrganic semiconductors exhibiting complementary-type carrier mobility are the key components for the development of the field of “gplastic electronics” We present here a novel series of α,ω- and isomerically pure ββ'-diperfluorohexyl-substituted thiophene and study the impact of fluoroalkyl substitution and conjugation length vis-a-vis the corresponding fluorinefree analogues. Trends between the fluorinated and fluorine-free families in molecular packing, HOMO-LUMO gap, and π-π interactions are found to be strikingly similar. TFT measurements indicate that all members of the fluorinated series are n-type semiconductors

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Elucidating the Impact of Molecular Packing and Device Architecture on the Performance of Nanostructured Perylene Diimide Solar Cells

ACS Applied Materials & Interfaces ◽

10.1021/acsami.5b00827 ◽

2015 ◽

Vol 7 (16) ◽

pp. 8687-8698 ◽

Cited By ~ 16

Author(s):

Eduardo Aluicio-Sarduy ◽

Ranbir Singh ◽

Zhipeng Kan ◽

Tengling Ye ◽

Aliaksandr Baidak ◽

...

Keyword(s):

Solar Cells ◽

Molecular Packing ◽

Perylene Diimide ◽

Device Architecture ◽

The Impact

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Tuning of Molecular Electrostatic Potential Enables Efficient Charge Transport in Crystalline Azaacenes: A Computational Study

10.20944/preprints202007.0149.v1 ◽

2020 ◽

Author(s):

Andrey Sosorev ◽

Dmitry Dominskiy ◽

Ivan Chernyshov ◽

Roman Efremov

Keyword(s):

Organic Semiconductors ◽

Electrostatic Potential ◽

Rational Design ◽

Molecular Electrostatic Potential ◽

Computational Study ◽

High Mobility ◽

Molecular Packing ◽

Frontier Molecular Orbital ◽

Charge Mobility ◽

The Impact

Chemical versatility of organic semiconductors provides nearly unlimited opportunities for tuning their electronic properties. However, despite decades of research, relationship between molecular structure, molecular packing and charge mobility in these materials remains poorly understood. This reduces the search for high-mobility organic semiconductors to the inefficient trial-and-error approach. For clarifying the abovementioned relationship, investigations of the effect of small changes in the chemical structure on OSs properties are particularly important. In this study, we address computationally the impact of substitution of C-H atom pairs by nitrogen atoms (N-substitution) on molecular properties, molecular packing and charge mobility of crystalline oligoacenes. Besides of decreasing frontier molecular orbital levels, N-substitution dramatically alters molecular electrostatic potential yielding pronounced electron-rich and electron-deficient areas. These changes in the molecular electrostatic potential strengthen face-to-face and edge-to-edge interactions in the corresponding crystals and result in the crossover from the herringbone packing motif to π-stacking. When the electron-rich and electron-deficient areas are large, sharply defined and, probably, have certain symmetry, charge mobility increases up to 3-4 cm2V-1s-1. The results obtained highlight the potential of azaacenes for application in organic electronic devices and are expected to facilitate rational design of organic semiconductors for steady improvement of organic electronics.

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Graded Morphologies and the Performance of PffBT4T-2OD:PC71BM Devices Using Additive Choice

Nanomaterials ◽

10.3390/nano11123367 ◽

2021 ◽

Vol 11 (12) ◽

pp. 3367

Author(s):

Hugo Gaspar ◽

Andrew J. Parnell ◽

Gabriel E. Pérez ◽

Júlio C. Viana ◽

Stephen M. King ◽

...

Keyword(s):

Power Conversion Efficiency ◽

Organic Semiconductors ◽

Conversion Efficiency ◽

Polymer Solar Cells ◽

Power Conversion ◽

Acid Methyl Ester ◽

Domain Size ◽

Grazing Incidence ◽

Exciton Diffusion Length ◽

The Impact

The impact of several solvent processing additives (1-chloronaphthalene, methylnaphthalene, hexadecane, 1-phenyloctane, and p-anisaldehyde), 3% v/v in o-dichlorobenzene, on the performance and morphology of poly[(5,6-difluoro-2,1,3-benzothiadiazol-4,7-diyl)-alt-(3,3‴-di(2-octyldodecyl)-2,2′,5′,22033,5″,2‴-quaterthiophen-5,5‴-diyl)] (PffBT4T-2OD):[6,6]-phenyl-C71-butyric acid methyl ester (PC71BM)-based polymer solar cells was investigated. Some additives were shown to enhance the power conversion efficiency (PCE) by ~6%, while others decreased the PCE by ~17–25% and a subset of the additives tested completely eliminated any power conversion efficiency and the operation as a photovoltaic device. Grazing-Incidence Wide Angle X-ray Scattering (GIWAXS) revealed a clear stepwise variation in the crystallinity of the systems when changing the additive between the two extreme situations of maximum PCE (1-chloronaphthalene) and null PCE (hexadecane). Small-Angle Neutron Scattering (SANS) revealed that the morphology of devices with PCE ~0% was composed of large domains with correlation lengths of ~30 nm, i.e., much larger than the typical exciton diffusion length (~12 nm) in organic semiconductors. The graded variations in crystallinity and in nano-domain size observed between the two extreme situations (1-chloronaphthalene and hexadecane) were responsible for the observed graded variations in device performance.

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Relationship between electron–phonon interaction and low-frequency Raman anisotropy in high-mobility organic semiconductors

Physical Chemistry Chemical Physics ◽

10.1039/c8cp03232g ◽

2018 ◽

Vol 20 (28) ◽

pp. 18912-18918 ◽

Cited By ~ 8

Author(s):

A. Yu. Sosorev ◽

D. R. Maslennikov ◽

I. Yu. Chernyshov ◽

D. I. Dominskiy ◽

V. V. Bruevich ◽

...

Keyword(s):

Raman Spectroscopy ◽

Organic Semiconductors ◽

Low Frequency ◽

High Mobility ◽

Phonon Interaction ◽

Electron Phonon Interaction ◽

The Impact

Raman spectroscopy and calculations probe the impact of low-frequency vibrations in anisotropic electron–phonon interaction.

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Impact of n-Doping Mechanisms on the Molecular Packing and Electron Mobilities of Molecular Semiconductors for Organic Thermoelectrics

Organic Materials ◽

10.1055/a-1729-5728 ◽

2022 ◽

Author(s):

Yan Zeng ◽

Guangchao Han ◽

Yuanping Yi

Keyword(s):

Charge Transfer ◽

Carrier Concentration ◽

Organic Semiconductors ◽

Electron Mobility ◽

Molecular Packing ◽

High Electron ◽

Mobility Of Charge Carriers ◽

N Doping ◽

Molecular Semiconductor ◽

The Impact

Electrical conductivity is one of the key parameters for organic thermoelectrics and depends on both the concentration and mobility of charge carriers. To increase the carrier concentration, molecular dopants have to be added into organic semiconductor materials, whereas the introduction of dopants can influence the molecular packing structures and hence carrier mobility of the organic semiconductors. Herein, we have theoretically investigated the impact of different n-doping mechanisms on molecular packing and electron transport properties by taking N-DMBI-H and Q-DCM-DPPTT respectively as representative n-dopant and molecular semiconductor. The results show that when the doping reactions and charge transfer spontaneously occur in the solution at room temperature, the oppositely charged dopant and semiconductor molecules will be tightly bound to disrupt the semiconductor to form long-range molecular packing, leading to a substantial decrease of electron mobility in the doped film. In contrast, when the doping reactions and charge transfer are activated by heating the doped film, the molecular packing of the semiconductor is slight affected and hence the electron mobility remains quite high. This work indicates that thermally-activated n-doping is an effective way to achieve both high carrier concentration and high electron mobility in n-type organic thermoelectric materials.

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Materials and Devices for Micro-invasive Neural Interfacing

MRS Advances ◽

10.1557/adv.2019.424 ◽

2019 ◽

Vol 4 (51-52) ◽

pp. 2805-2816 ◽

Cited By ~ 1

Author(s):

Khalil B. Ramadi ◽

Michael J. Cima

Keyword(s):

Tissue Damage ◽

Emerging Technologies ◽

Form Factors ◽

Significant Benefit ◽

Design Parameters ◽

Popular Interest ◽

Glial Scarring ◽

The Impact ◽

Probe Insertion ◽

Neural Interfacing

ABSTRACTThere is widespread research and popular interest in developing micro-invasive neural interfacing modalities. An increasing variety of probes have been developed and reported in the literature. Newer, smaller probes show significant benefit over larger ones in reducing tissue damage and scarring. A different set of obstacles arise, however, as probes become smaller. These include reliable insertion and robustness. This review articulates the impact of various design parameters (material, geometry, size) on probe insertion mechanisms, chronic viability, and glial scarring. We highlight various emerging technologies utilizing novel form factors including micron-scale interfaces and bio-inspired designs for probe insertion and steering.

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