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We show that the thermal and electrical properties of single wall carbon nanotube (CNT)-polymer composites are significantly enhanced by magnetic alignment during processing. The electrical transport properties of the composites are mainly governed by the hopping conduction with localization lengths comparable to bundle diameters. The bundling of nanotubes during the composite processing is an important factor for electrical, and in particular, for thermal transport properties. Better CNT isolation will be needed to reach the theoretical thermal conductivity limit for CNT composites.

In this work, we synthesized novel hole transporting materials (HTMs) and we studied their impact on the stability of perovskite-based solar cells (PSCs). The steady-state maximum power output of devices in working condition was monitored to assess the stability and to predict the lifetime of PSCs prepared with different HTMs. We showed that the HTM has significant impact on the device lifetime and we found that novel silolothiophene linked methoxy triphenylamines (Si-OMeTPA) enable more stable PSCs. We reported Si-OMeTPA based devices with half-life of 6 Khrs, compared to 1 Khrs collected for the state-of-the-art PSCs using spirofluorene linked methoxy triphenylamines (spiro-OMeTAD) as HTM. We demonstrated that such clear improvement is correlated to the superior thermal stability of silolothiophene compared to the spiro linked triphenylamines HTMs. Figure 6. Current-voltage curves of the solar cells collected under AM1.5 simulated sun light.Devices were masked with a metal aperture of 0.16 cm 2 to define the active area. The curves were recorded scanning at 0.01 V s -1 from forward bias (FB) to short circuit condition (SC) and the other way around.

Carbon nanotubes possess exceptional mechanical properties and superior thermal and electric properties.[1±4] Hence, nanotubes can be ideal reinforcement fibers for structural composites. For example, a cast composite film consisting of polystyrene and carbon nanotubes (5 % volume fraction) has increased the modulus by 100 % and the strength of the polystyrene by 25 %.[5] Moreover, the carbon nanotubes reinforcement increased the toughness of the composite by absorbing energy because of their high elastic behavior during loading.

When supported upon dehydroxylated (DA) or partially dehydroxylated (PDA) alumina, the organozirconium complexes (C5H6)2Zr(CH3)2 (1), [(CH3)5C5]2Zr(CH3)2 (2), and [(CH3)5C5]Zr(CH3)3 (3) are highly active catalysts for propylene hydrogenation. Turnover frequencies (s-1) at -63 °C (DA, PDA) are as follows:for 1, 0.3, 0.1; for 2, 0.2, 0.06; and for 3, 1.1, 0.3. CO poisoning experiments indicate 54% of 1/DA and 512% of 3/DA Zr sites are catalytically active. Ethylene polymerization activity follows the order 3 » 1=2, and DA > PDA. Solid-state 13C CPMAS NMR spectra of (C6H5)2Zr(*CH3)2/DA and (C5H5)2Zr-(*CH3)2/PDA (*C = 90% 13C) evidence *CH3 transfer to A1 surface sites and formation, inter alia, of Cp2Zr(*CH3)+ species. Such processes also occur on PDA.