炭素ベースの分子交差点で60nm以上の光刺激付近共振電荷輸送
Shailendra K Saxena1, Ushula M Tefashe1, Richard L McCreery1
1Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada.
Journal of the American Chemical Society
|August 14, 2020
まとめ
光誘導電流は 暗い電流よりも 大きさの順番が大きいので 先進的な分子電子学の 新しい輸送メカニズムを明らかにします
科学分野:
- 分子電子
- オーガニックの電子機器
- 材料科学
背景:
- 先進的な電子機器の開発には 分子結合における電荷輸送機構の理解が不可欠です
- 炭素基の分子結合は 電子的な用途に ユニークな特性を備えています
- これらの交差点における電流の厚さと温度依存は,調査する重要なパラメータです.
研究 の 目的:
- 炭素基の分子結合における暗と光誘導電流のバイアスと温度依存性を調査する.
- オリゴメア層の厚さの範囲にわたるニトロアゾベンゼン分子結合における電荷輸送メカニズムを解明する.
- 光誘導電流と暗い電流の行動を比較する.
主な方法:
- 異なるオリゴメール層の厚さ (460 nm) を有する炭素ベースの分子結合の製造と特徴付け.
- ダークとフォト誘導電流の両方の電流密度対バイアス (JV) と温度依存性の測定.
- 電場と厚さとの関係における電流の振る舞いの分析.
主要な成果:
- ダーク電流は,薄層 (<5 nm) の指数関数的な厚さ依存性と,より厚い層 (1560 nm) の弱い依存性を示しています.
- 光誘導電流はダーク電流よりも著しく高く,異なるバイアス依存性を表しています.
- 暗い電流と光誘導電流は,厚さ>14 nmで電場に依存し,200 K以下では活性化なしの行動を示します.
結論:
- 分子軌道間の連続トンネリングを含む軌道媒介輸送は,光誘導電流のために提案されています.
- ダーク電流はインターフェイスエネルギーバリアによって制限され,光誘導電流は量的に制限されます.
- これらの発見は,高速で低バリアの輸送は,分子電子の動作範囲を50 nmを超えることを示唆しています.
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