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The unconventional self-assembled nanodielectric (SAND) architecture is composed of solution-processed alternating inorganic (e.g., ZrOx and HfOx) and π-organic nanolayers (e.g., stilbazolium). As gate dielectrics, SANDs are compatible with a wide variety of organic and inorganic semiconductors and often impart superior thin-film transistor (TFT) performance in comparison to analogous inorganic-only dielectrics. The enhanced performance has been partly attributed to the interactions within the organic layers. To probe the role of the highly polarizable stilbazolium (Chr) organic layer in SAND structural organization and dielectric response, a saturated hydrocarbon chain-based self-assembling building block (Alk) was synthesized and incorporated in SAND structures. By using Chr and Alk in the different SAND organic layers, the effects of the Chr built-in dipole on bulk SAND structural and dielectric characteristics can be evaluated. The Zr-SAND structures are characterized by atomic force microscopy, X-ray reflectivity, metal-insulator-semiconductor electrical measurements, and pentacene-based organic TFTs. The layer identity and arrangement of the organic layers within the Zr-SAND structure are found to have a significant impact on the capacitor leakage current and pentacene transistor threshold voltage/turn-on voltage characteristics. Furthermore, significant cooperative interactions between adjacent Chr organic π-layers are important in enhancing these effects.

The development of cheap and reliable time-temperature indicators (TTIs) can greatly improve customer satisfaction with respect to the correct handling and storage of perishable goods. A series of new irreversible thermochromic squaraine dyes enables the preparation of simple TTIs whose time-temperature regime can be controlled by selection of the appropriate molecule/substrate combinations.

The influence of solubilizing substituents on the photovoltaic performance and thin-film blend morphology of new benzo[1,2-b:6,5-b']dithiophene (bBDT) based small molecule donor semiconductors is investigated. Solar cells based on bBDT(TDPP)2-PC71BM with two different types of side chains exhibit high power conversion efficiencies, up to 5.53%.

Highly efficient plastic based single layer Luminescent Solar Concentrators (LSCs) require the design of luminophores having complete spectral separation between absorption and emission spectra (large Stokes shift). We describe the design, synthesis and characterization of a new perylene dye possessing Stokes shift as high as 300 meV, fluorescent quantum yield in the LSC slab of 70% and high chemical and photochemical stability. © 2013 The Royal Society of Chemistry.