関連する実験動画
Updated: Oct 3, 2025
05:33
Solid-state Graft Copolymer Electrolytes for Lithium Battery Applications
Published on: August 12, 2013
21.8K
構造と動的障害,非イオン捕獲,高ドーピング導体ポリマーの電荷輸送を制御する
Ian E Jacobs1, Gabriele D'Avino2, Vincent Lemaur3
1Optoelectronics Group, Cavendish Laboratory, University of Cambridge, J J Thomson Avenue, Cambridge CB3 0HE, U.K.
Journal of the American Chemical Society
|February 14, 2022
まとめ
ドーピングされた有機半導体の低伝導性は,ドーピングカウンターイオンによる電荷捕獲によるものではない. 代わりに,パラクリスタルの乱れは電気伝導性を制限し,材料の改善のための新しい戦略を提供します.
科学分野:
- 材料科学
- 凝縮物質物理学
- オーガニック電子
背景:
- 熱電学や ニューロモルフィック・コンピューティングなどの 先進的な装置に不可欠です
- 現在の理解では,低伝導性は主にドーパントカウンターイオンによる電荷捕獲に起因する.
研究 の 目的:
- ドーピングされた有機半導体の電気伝導性を制限する主要な要因を調査する.
- ドーパントカウンターイオンのクーロンポテンシャルが低伝導性の主な原因であるという一般的な仮定に異議を唱える.
主な方法:
- 新しいイオン交換ドーピング技術を活用して 高度ドーピングされた有機半導体フィルムを作りました
- 様々なポリマー-イオン組合せにおけるキャリア密度,電気伝導性,およびパラクリスタル性障害の特徴.
- 原子学的な計算によって検証された,一時的な局所化理論に基づく理論的モデルを開発し,適用した.
主要な成果:
- 電気伝導性はパラ結晶性障害との強い相関を示した.
- 導電性は,ドーパントカウンターイオンのサイズと形との相関が悪いことを示した.
- 理論的な計算は 実験結果と完璧に一致しました
結論:
- ドーパントカウンターからのクーロントラップは,これらの材料における電荷輸送を大幅に制限しません.
- 超結晶性障害は,高度にドーピングされた有機半導体における電気伝導性を支配する要因である.
- 材料の乱れを制御することで伝導性を高める新しい方法が示唆されています.
関連する概念動画
01:21Polymer Classification: Crystallinity
3.2K
Unlike ionic or small covalent molecules, polymers do not form crystalline solids due to the diffusion limitations of their long-chain structures. However, polymers contain microscopic crystalline domains separated by amorphous domains.
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
3.2K
01:21Carrier Transport
623
The generation of electrical current in semiconductors is fundamentally driven by two mechanisms: drift and diffusion. These processes are essential for the functionality and performance of semiconductor-based devices.
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by:
623
00:57Cationic Chain-Growth Polymerization: Mechanism
2.4K
The cationic polymerization mechanism consists of three steps: initiation, propagation, and termination. In the initiation step of the polymerization process, the π bond of a monomer gets protonated by the Lewis acid catalyst, which is formed from boron trifluoride and water. The protonation of the π bond generates a carbocation stabilized by the electron‐donating group. In the propagation step, the π bond of the second monomer acts as a nucleophile and attacks the...
2.4K
01:04Anionic Chain-Growth Polymerization: Mechanism
2.1K
The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael...
2.1K
01:29Potential Due to a Polarized Object
496
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...
496
01:14Polymer Classification: Architecture
3.1K
Polymers are classified as linear or branched on the basis of their chain architecture. The polymer chains in linear polymers have a long chain-like structure with minimal to no branching at all. Even if a polymer features large substituent groups on the monomer, which appear as branches to the skeleton, it is not considered a branched polymer. A branched polymer contains secondary polymer chains that arise from the main polymer chain. The branching occurs when the polymer growth shifts from...
3.1K