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Highlights: [•] Solar cells with PPy:PSS have performance as with PEDOT:PSS. [•] PPy:PSS does not etch ITO since there is no PSSH, opposite to PEDOT:PSS. [•] PPy:PSS offers the opportunity for longer-life devices than PEDOT:PSS. [•] Electrodepositing PPy:PSS easy/precise control of film thickness/device performance. [•] PPy:PSS electrodeposited using general electrical equipment no investments required. [ABSTRACT FROM AUTHOR]

Abstract: The use of carbon nanotube-fullerene hybrid additives to the standard P3HT:PCBM blend bulk-heterojunction organic photovoltaic device is presented. The effects of incorporating single-wall carbon nanotubes, functionalized with linked C60 molecules by amination on device characteristics are detailed. The concentration of the carbon nanotube-fullerene hybrid in the active layer blend was varied to ascertain their cumulative impact on device performance in terms of open circuit voltage, short circuit current, fill factor and efficiency. We found that decreasing the length of the carbon nanotubes to ∼60nm through fluorination and subsequent thermal treatment was beneficial in terms of eliminating shorted devices allowing much improved diode formation. A trend of improving device performance as a function of concentration of the carbon nanotube-hybrids in a heterojunction of P3HT:PCBM was observed. [Copyright &y& Elsevier]

Abstract: We have prepared p–n junction organic photovoltaic cells using an all solution processing method with poly(3-hexylthiophene) (P3HT) as the donor and phenyl-C61-butyric acid methyl ester (PCBM) as the acceptor. Interdigitated donor/acceptor interface morphology was observed in the device processed with the lowest boiling point solvent for PCBM used in this study. The influences of different solvents on donor/acceptor morphology and respective device performance were investigated simultaneously. The best device obtained had characteristically rough interface morphology with a peak to valley value ∼15nm. The device displayed a power conversion efficiency of 1.78%, an open circuit voltage (V oc) 0.44V, a short circuit current density (J sc) 9.4mA/cm2 and a fill factor 43%. [Copyright &y& Elsevier]

Abstract: Solid polymer gel electrolytes composed of 75wt.% of the ionic liquid, 1-n-butyl-2,3-dimethylimidazolium bis-trifluoromethanesulfonylimide with 1.0M lithium bis-trifluoromethanesulfonylimide and 25wt.% poly(vinylidenedifluoro-hexafluoropropene) are characterized as the electrolyte/separator in solid-state lithium batteries. The ionic conductivity of these gels ranges from 1.5 to 2.0mScm−1, which is several orders of magnitude more conductive than any of the more commonly used solid polymers, and comparable to the best solid gel electrolytes currently used in industry. TGA indicates that these polymer gel electrolytes are thermally stable to over 280°C, and do not begin to thermally decompose until over 300°C; exhibiting a significant advancement in the safety of lithium batteries. Atomic force microscopy images of these solid thin films indicate that these polymer gel electrolytes have the structure of nano-sponges, with a sub-micron pore size. For these thin film batteries, 150 charge–discharge cycles are run for Li x CoO2 where x is cycled between 0.95 down to 0.55. Minimal internal resistance effects are observed over the charging cycles, indicating the high ionic conductivity of the ionic liquid solid polymer gel electrolyte. The overall cell efficiency is approximately 98%, and no significant loss in battery efficiency is observed over the 150 cycles. [Copyright &y& Elsevier]

A series of para-substituted dianilino[24]crown-8 (DA24C8) macrocycles were synthesized and their ability to form host–guest complexes with bis(4-fluorobenzyl)ammonium ions (DFA+) were investigated. Although these crown ethers contain weakly hydrogen bonding aniline motifs, they do bind DFA+ in CDCl3/CD3NO2 solution, presumably in a pseudorotaxane-like manner. A plot of the values of the relative binding strengths (log[Ka(R)/Ka(H)]) versus the Hammett substituent constants σ+ of the groups at the para-position of the aniline units suggests that a linear free energy correlation exists for this self-assembly process. The strength of the binding between the crown ether and the thread-like ion can be fine-tuned over a narrow range by judicious choice of the substituting groups. [Copyright &y& Elsevier]

• Solar reflective coating based on functionalized anatase TiO 2 particles incorporated in an organosiloxane matrix (TiO 2 /sol) is prepared via a sol-gel method. • Organosiloxane coating exhibits excellent hydrophobicity, static friction, and durability. • Temperature reduction inside the concrete mortar composite specimens treated with TiO 2 /sol records as high as 4.1 °C (8.0 °F) compared to its pristine state sample. • Efficient light scattering by embedded TiO 2 particles is the mechanism for temperature reduction. This paper reports the synthesis and investigation of the effectiveness of a solar reflective coating designed for building materials having properties, such as substrate penetration, water repellency, slip resistance, durability, and reduction of heat in the buildings. The coating was synthesized via stabilization and incorporation of anatase TiO 2 particles in an organosiloxane matrix using a sol–gel technique. Organosiloxane matrices are transparent and easy to process, which makes them an ideal host material to immobilize and incorporate TiO 2 particles as scattering centers, which have a high index of refraction (2.5–2.7). For this reason, functional inorganic–organic hybrid composite materials are excellent candidates for novel solar reflective coatings. In application, the coating also acts as a multifunctional protective layer for building materials. In this work, we characterize various functionalities of the organosiloxane coating, including surface hydrophobicity, static friction, and durability. We observed the temperature reduction of 4.1 °C (8 °F) inside the cement mortar composite (CMC) treated with such coating, exhibiting excellent hydrophobicity, slip resistance, and longevity. The significant reduction in temperature is attributed to efficient light scattering by embedded TiO 2 particles. [ABSTRACT FROM AUTHOR]