A Sterically Hindered Phosphonic Acid with a Hydrogen-Bonded Cage Structure: [4-tert-Bu-2,6-Mes2-C6H2P(O)(OH)2·H2O]4

P-C bond formation via P-H addition of a fluoroaryl phosphinic acid to ketones

The synthesis, structure and reactivity of the fluoroaryl phosphinic acid HF(4)C(6)-P(O)HOH is reported and compared to a sterically comparable yet non-fluorinated analog with similar size. The fluoroaryl phosphinic acid undergoes reversible P-H addition to the carbonyl functionality of ketones under formation of a P-C bond which is retained in the resulting α-hydroxy phosphinic acid. The latter shows an extended 2D hydrogen bonded network in the solid state.

Oligo- and polythiophene/ZnO hybrid nanowire solar cells

We demonstrate the basic operation of an organic/inorganic hybrid single nanowire solar cell. End-functionalized oligo- and polythiophenes were grafted onto ZnO nanowires to produce p-n heterojunction nanowires. The hybrid nanostructures were characterized via absorption and electron microscopy to determine the optoelectronic properties and to probe the morphology at the organic/inorganic interface. Individual nanowire solar cell devices exhibited well-resolved characteristics with efficiencies as high as 0.036%, J(sc) = 0.32 mA/cm(2), V(oc) = 0.4 V, and a FF = 0.28 under AM 1.5 illumination with 100 mW/cm(2) light intensity. These individual test structures will enable detailed analysis to be carried out in areas that have been difficult to study in bulk heterojunction devices.