光と電場を持つTiO2表面に分子を転がす
Renato N Sampaio1, Guocan Li1, Gerald J Meyer1
1Department of Chemistry , The University of North Carolina at Chapel Hill , Murray Hall 2202B , Chapel Hill , North Carolina 27599-3290 , United States.
Journal of the American Chemical Society
|August 1, 2019
まとめ
光はTiO2の染料分子を反転させ 再び反転させます 太陽電池の電荷再結合に影響します 太陽電池の電荷再結合は
科学分野:
- 材料科学
- 写真化学
- ナノテクノロジー
背景:
- 染料感知太陽電池 (Dye-sensitized solar cells, DSSC) は,感知器から半導体酸化物への効率的な電子転送に依存しています.
- 半導体インターフェイスでの分子行動を理解することは,デバイスの性能を最適化するために不可欠です.
- 興奮状態によって生成される電場が分子指向に果たす役割は完全に理解されていない.
研究 の 目的:
- TiO2に固定されたルテニウムベースの感知器の光誘発的方向転換 (フリッピング) を調査する.
- この分子反転が 荷重再結合のダイナミクスに与える影響を 調べました
- 半導体界面における電場が 分子運動を誘導する役割を調査する.
主な方法:
- アナタゼTiO2ナノ結晶に対する[Ru (NH3) 5 (eina) ] (PF6) 2感受剤のスペクトル解析.
- フリッピングと充電再結合を監視するためにパルス光刺激を用いた時間解決試験.
- 感知器の方向性に対する熱還元効果を調査するためのスペクトロ電気化学測定.
主要な成果:
- 光刺激によって感知器の反転と興奮状態の電子注入が誘発される.
- カーボキシル酸誘導体やSnO2/TiO2コア/シェル構造では,フリッピングは存在しなかった.
- 荷重再結合は酸化感受器が反転したときにより速く,より強い電子結合を示しました.
- リコンビネーション (26. 7) とフリッピング (0. 12) のための動態同位体効果が測定されました.
- 熱還元は反転を誘発しますが,光刺激よりもはるかに高い電場を必要とします.
結論:
- 照らされた半導体インターフェイスで発生する電場は,表面に固定された分子を方向転換するのに十分です.
- 感知器の反転は,電荷再結合率に大きく影響し,デバイスの全体的な効率に影響します.
- この発見は,ナノマテリアルにおけるインターフェイスの電荷伝送メカニズムと分子ダイナミクスに関する洞察を提供します.
関連する概念動画
01:26Electric Field at the Surface of a Conductor
5.2K
Consider a conductor in electrostatic equilibrium. The net electric field inside a conductor vanishes, and extra charges on the conductor reside on its outer surface, regardless of where they originate.
In the 19th century, Michael Faraday conducted the famous ice pail experiment to prove that the charges always reside on the surface of a conductor. The experimental set-up consists of a conducting uncharged container mounted on an insulating stand. The outer surface of the container is...
In the 19th century, Michael Faraday conducted the famous ice pail experiment to prove that the charges always reside on the surface of a conductor. The experimental set-up consists of a conducting uncharged container mounted on an insulating stand. The outer surface of the container is...
5.2K
01:16Electric Field
12.3K
Consider two point charges, each exerting Coulomb force on the other. It is possible to describe the Coulomb interaction via an intermediate step by defining a new physical quantity called the electric field.
In the new picture, imagine that the first charge sets up an electric field independent of all other charges in the universe. When another charge comes in its vicinity, the second charge experiences an electric force depending on the electric field at that point. The source charge does not...
In the new picture, imagine that the first charge sets up an electric field independent of all other charges in the universe. When another charge comes in its vicinity, the second charge experiences an electric force depending on the electric field at that point. The source charge does not...
12.3K
01:12Determining Electric Field From Electric Potential
4.9K
The electric field and electric potential are related to each other. If the electric field at various points in the region of interest is known, it can be used to calculate the electric potential difference between any two points. Similarly, if the electric potential is known for various points, then it is possible to calculate the electric field.
In general, regardless of whether the electric field is uniform, it points in the direction of decreasing potential because the force on a positive...
In general, regardless of whether the electric field is uniform, it points in the direction of decreasing potential because the force on a positive...
4.9K
01:13Finding Electric Potential From Electric Field
5.4K
For a system of charges, it is easy to calculate the system's potential because potential is a scalar quantity. However, in some instances where calculating the electric field is more straightforward than finding the potential, the electric field is used to calculate the system's potential. For a positive charge, the electric field is radially outward, and the potential is positive at any finite distance from the positive charge. In such an electric field, the motion away from the...
5.4K
01:20Electric Field Inside a Conductor
7.3K
When a conductor is placed in an external electric field, the free charges in the conductor redistribute and very quickly reach electrostatic equilibrium. The resulting charge distribution and its electric field have many interesting properties, which can be investigated with the help of Gauss's law.
Suppose a piece of metal is placed near a positive charge. The free electrons in the metal are attracted to the external positive charge and migrate freely toward that region. This region then...
Suppose a piece of metal is placed near a positive charge. The free electrons in the metal are attracted to the external positive charge and migrate freely toward that region. This region then...
7.3K
01:25Electric Field Lines
9.3K
The three-dimensional representation of the electric field of a positive point charge requires tracing the electric field vectors, whose lengths decrease as the square of their distance from the charge and which point away from the charge at each point. This vector field is no doubt challenging to visualize. The visualization of electric fields becomes quickly intractable as the number of charges increases.
The solution to this problem is to use electric field lines, which are not vectors but...
The solution to this problem is to use electric field lines, which are not vectors but...
9.3K