Bridge-Dependent Interfacial Electron Transfer (2011)

Tue, 22 Mar 2011 11:22:29 -0500

Top: The kinetics of charge transfer from a rhenium-bypyridine complex to a TiO2 , measured for several molecular linkers (purple, black, red, and blue traces). Insets show the structure of the molecular systems, and infrared spectroscopy demonstrating the attachment of Re1C to TiO2.

Bottom: Calculated transition densities associated with the 1MLCT excited state (left, shown for the ReEC complex) and biothiophene Ïï®Ï* transition (right, Re2TC complex). The green shows areas of electron density depletion, and the yellow areas of excess density.

[Image461]Charge transfer across interfaces has an important fundamental role in materials with applications ranging from solar energy to photocatalysis. In dye sensitized solar cells, electrons are excited in a dye molecule by the absorption of light and subsequently injected into an inorganic semiconductor. IRG2 has resolved the electron injection kinetics of the dye sensitizer by optically probing the electrons transferred to TiO2 nanocrystal from a rhenium dye by using a mid-infrared....

Mechanisms of Organic/Inorganic Interface Formation (2011)

Tue, 22 Mar 2011 11:17:42 -0500

Left: (a) STM image of the Si(001) 2 x 1 surface prior to exposure to nitrobenzene. (b) STM image after exposure to 30 Langmuir of nitrobenzene. The inset arrow in (b) indicates the direction of the rows of nitrobenzene molecules, which are perpendicular to the substrate dimer rows.

Right: Potential energy surface of the structural evolution of nitrobenzene adsorbed on Si(001) at 1 ML coverage. Numbers in blue give the relative heights of the topmost H of the phenyl ring referenced to the height of that atom in the NO2 configuration. Numbers in black and red give the activation energy barrier in eV for the transformations between configurations shown in the insets.

Advanced organic/inorganic materials for applications including solar energy conversion and optoelectronics require the creation of interfaces with carefully controlled structural and electronic properties. Functional monolayers at these interfaces can have associated electronic states or dipole moments and thus provide a new degree of control over device properties. IRG 2 has already shown how functional interfaces incorporating electron acceptors and reconfigurable molecular dipoles can....

UW MRSEC IRG 2 Nuggets

Bridge-Dependent Interfacial Electron Transfer (2011)

Mechanisms of Organic/Inorganic Interface Formation (2011)