Light and electric field induced unusual large-scale charge separation in hybrid semiconductor objects

Ambrose Melvin (1) , Eric Lebraud (2) , Patrick Garrigue (1) , Alexander Kuhn (3)

1 ISM - Institut des Sciences Moléculaires
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux
3 Bordeaux INP - Institut Polytechnique de Bordeaux

Separation of electric charges is the most crucial phenomenon in natural photosynthesis, and also extremely important for many artificial energy conversion systems based on semiconductors. The usual roadblock in this context is the fast recombination of electrons and holes. Here we demonstrate that the synergy of light and electric fields allows separating very efficiently electric charges over an unusually large distance in TiO2. The generated internal electric field can also be used to shuttle electrons simultaneously to the two opposite sides of a hybrid TiO2-polyaniline object. This counterintuitive behavior is based on the combination of the principles of bipolar electrochemistry and semi-conductor physics.

Mots clés: Bipolar electrochemistry; semiconductors; electrodeposition; photoelectrochemistry; charge separation

Domaines: Chimie

Ambrose Melvin, Eric Lebraud, Patrick Garrigue, Alexander Kuhn. Light and electric field induced unusual large-scale charge separation in hybrid semiconductor objects. Physical Chemistry Chemical Physics, 2020, ⟨10.1039/D0CP03262J⟩. ⟨hal-02938181⟩