TiO2 Anatase Solutions for Electron Transporting Layers in Organic Photovoltaic Cells.

Reflux of a solution of [Ti8 O12 (H2 O)24 ]Cl8 ⋅HCl⋅7 H2 O as titanium precursor at 120 °C for 24 h leads to a transparent colloidal solution of nanosized crystallized anatase TiO2 . The adjustment of the particle size and composition of the dispersant is monitored through the initial water content while controlling the conversion of propylene carbonate into propylene glycol during reflux. The solutions were processed as thin films to produce electron transporting layers in hybrid bulk heterojunction solar cells, by using a blend of P3HT:PCBM polymers as absorbers, in inverted architectures. The solutions obtained by reflux were demonstrated to produce suitable electron transporting layers.

Rodlike fluorescent pi-conjugated 3,3'-bipyridazine ligand: optical, electronic, and complexation properties.

We report on the design and synthesis of a new quadrupolar pi-conjugated 3,3'-bipyridazine D-A-D ligand. Its electronic and optical properties were investigated. Besides high fluorescence and pronounced solvatochromism, it exhibits an inherent electroactivity exploited to build an organic green light emitting device. Moreover, the ability of this ligand to complex metallic centers (Cu(I), Ni(II), Pt(II), and Ir(III)) was also investigated to access different geometries and to tune their electronic and optical properties. These preliminary results open up the synthesis of heavy-metal complexes to obtain phosphorescent emitters.